React State and Props

What is the main purpose of props in React?

• To store and manage data within a component

• To pass data from one component to another

• To modify the state of a component

Which of the following would correctly render a list of items in React using the map() method?

• {

  items.forEach((item) => <li>{item}</li>

  )

  }

• • {

  • items.map(<li>{item}</li>)

  • }

• • {

  • items.map((item) =>

  • <li key={item.id}>{item}</li>)

  • }

What happens if you don’t use a unique key for list items in React?

• • The list will not render at all.

• • React will throw an error and stop rendering.

• • React may have trouble updating the list efficiently.

What is the correct syntax of useState in react?

• const [state, setState] = useState(initialValue);

• const state = useState(initialValue);

• const [state setState] = useState(initialValue);

Given the array

const students = [{ name: "Alice" }, { name: "Bob" }]

which is the correct way to access the name property of the first item?

• students.name[0]

• students[0].name

• students(0).name

Which of the following would be a valid way to pass props to a child component in React?

• <ChildComponent props="Hello" />

• <ChildComponent message="Hello" />

• ChildComponent {message}="Hello" />

What is the purpose of state in a React component?

• • It contains the component’s initial HTML structure.

• • It passes data to child components.

• • It stores the data that can change over time and causes re-rendering.