React - Graded Quiz

10. What is the purpose of the useEffect Hook in React?

  • To handle events in a component.
  • To manage state in a component.
  • To run side effects in a component.
  • To render a component to the DOM.

11. Which lifecycle method in React is equivalent to the useEffect Hook?

  • componentDidMount
  • componentDidUpdate
  • componentWillUnmount
  • Both componentDidMount and componentDidUpdate

12. What is the purpose of the dependency array in the useEffect Hook?

  • To specify the state variables that should trigger the effect.
  • To specify the state variables that the effect depends on.
  • To specify the props that the effect depends on.
  • Both B and C.

13. What is the purpose of the "querySelector()" method in JavaScript?

  • To select and remove an HTML element from the DOM.
  • To create a new HTML element based on a CSS selector.
  • To select and retrieve the value of an attribute from an HTML element.
  • To select and retrieve the first matching HTML element from the DOM based on a CSS selector.

14. Which method is used to add an HTML element to the DOM in JavaScript?

  • removeChild()
  • createElement()
  • replaceChild()
  • appendChild()

15. What is the purpose of the useContext hook in React?

  • To manage the state of a component.
  • To perform side effects in a component, such as fetching data or updating the DOM.
  • To provide data to a component from a global state.
  • To connect a component to a Redux store.

16. Which hook is used to handle side effects in a React component?

  • useState
  • useEffect
  • useContext
  • useReducer

17. Which argument is passed to the useEffect hook to specify when the effect should be run?

  • A function to run before the effect is run.
  • An object representing the dependencies of the effect.
  • A function to run after the effect is run.
  • An array of values to be passed to the effect.

18. Which hook is used to connect a React component to a Redux store?

  • useState
  • useEffect
  • useContext
  • useDispatch

19. What is the purpose of the "map()" method in JavaScript?

  • To iterate over the keys of an object.
  • To filter elements of an array based on a condition.
  • To sort elements of an array in ascending order.
  • To transform each element of an array and create a new array based on the returned values.

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