18 Components & JSX questions from the React bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.a syntax extension that compiles to React.createElement calls describing the UI
B.read-only inputs passed from a parent component down to a child
C.a stable identity React uses to match list items across renders for efficient reconciliation
D.a <>...</> wrapper that groups children without adding an extra DOM node
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2. Which term means: "a syntax extension that compiles to React.createElement calls describing the UI"?
Junior
A.Fragment
B.Props
C.Component
D.JSX
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.JSX — a function that returns JSX for React to render and receives props as its input
B.JSX — a form input whose value is driven by React state rather than by the DOM
C.JSX — a syntax extension that compiles to React.createElement calls describing the UI
D.JSX — a stable identity React uses to match list items across renders for efficient reconciliation
Answer + AI explanation with Pro
4. What is Component?
Junior
A.a <>...</> wrapper that groups children without adding an extra DOM node
B.a function that returns JSX for React to render and receives props as its input
C.a syntax extension that compiles to React.createElement calls describing the UI
D.a stable identity React uses to match list items across renders for efficient reconciliation
Answer + AI explanation with Pro
5. Which term means: "a function that returns JSX for React to render and receives props as its input"?
Junior
A.Fragment
B.Controlled component
C.Props
D.Component
Answer + AI explanation with Pro
6. Which statement is correct?
Junior
A.Component — a form input whose value is driven by React state rather than by the DOM
B.Component — a syntax extension that compiles to React.createElement calls describing the UI
C.Component — a <>...</> wrapper that groups children without adding an extra DOM node
D.Component — a function that returns JSX for React to render and receives props as its input
Answer + AI explanation with Pro
7. What is Props?
Junior
A.read-only inputs passed from a parent component down to a child
B.a form input whose value is driven by React state rather than by the DOM
C.a syntax extension that compiles to React.createElement calls describing the UI
D.a <>...</> wrapper that groups children without adding an extra DOM node
Answer + AI explanation with Pro
8. Which term means: "read-only inputs passed from a parent component down to a child"?
Junior
A.JSX
B.Fragment
C.Props
D.Component
Answer + AI explanation with Pro
9. Which statement is correct?
Junior
A.Props — a syntax extension that compiles to React.createElement calls describing the UI
B.Props — a <>...</> wrapper that groups children without adding an extra DOM node
C.Props — a stable identity React uses to match list items across renders for efficient reconciliation
D.Props — read-only inputs passed from a parent component down to a child
Answer + AI explanation with Pro
10. What is key prop?
Mid
A.a syntax extension that compiles to React.createElement calls describing the UI
B.a <>...</> wrapper that groups children without adding an extra DOM node
C.a function that returns JSX for React to render and receives props as its input
D.a stable identity React uses to match list items across renders for efficient reconciliation
Answer + AI explanation with Pro
11. Which term means: "a stable identity React uses to match list items across renders for efficient reconciliation"?
Mid
A.key prop
B.JSX
C.Fragment
D.Props
Answer + AI explanation with Pro
12. Which statement is correct?
Mid
A.key prop — a stable identity React uses to match list items across renders for efficient reconciliation
B.key prop — a function that returns JSX for React to render and receives props as its input
C.key prop — a form input whose value is driven by React state rather than by the DOM
D.key prop — read-only inputs passed from a parent component down to a child
Answer + AI explanation with Pro
13. What is Fragment?
Junior
A.a function that returns JSX for React to render and receives props as its input
B.a syntax extension that compiles to React.createElement calls describing the UI
C.a <>...</> wrapper that groups children without adding an extra DOM node
D.a stable identity React uses to match list items across renders for efficient reconciliation
Answer + AI explanation with Pro
14. Which term means: "a <>...</> wrapper that groups children without adding an extra DOM node"?
Junior
A.JSX
B.Props
C.Component
D.Fragment
Answer + AI explanation with Pro
15. Which statement is correct?
Junior
A.Fragment — a <>...</> wrapper that groups children without adding an extra DOM node
B.Fragment — read-only inputs passed from a parent component down to a child
C.Fragment — a syntax extension that compiles to React.createElement calls describing the UI
D.Fragment — a function that returns JSX for React to render and receives props as its input
Answer + AI explanation with Pro
16. What is Controlled component?
Mid
A.read-only inputs passed from a parent component down to a child
B.a form input whose value is driven by React state rather than by the DOM
C.a syntax extension that compiles to React.createElement calls describing the UI
D.a <>...</> wrapper that groups children without adding an extra DOM node
Answer + AI explanation with Pro
17. Which term means: "a form input whose value is driven by React state rather than by the DOM"?
Mid
A.Controlled component
B.Fragment
C.Component
D.Props
Answer + AI explanation with Pro
18. Which statement is correct?
Mid
A.Controlled component — a stable identity React uses to match list items across renders for efficient reconciliation
B.Controlled component — a form input whose value is driven by React state rather than by the DOM
C.Controlled component — a function that returns JSX for React to render and receives props as its input
D.Controlled component — a <>...</> wrapper that groups children without adding an extra DOM node
Answer + AI explanation with Pro
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