React Hooks useContext and useReducer

Question 1

What must you create before using the useContext hook?

Accepted Answer

A context object with React.createContext

Answer

A Redux store

Answer

A global variable

Answer

A class component

Question 2

What does the useContext hook return?

Accepted Answer

The nearest Provider's value prop

Answer

The Context object

Answer

A [value, setValue] tuple

Answer

The default value only

Question 3

When does a component using useContext re-render?

Accepted Answer

When the Provider's value prop changes

Answer

Never automatically

Answer

Only on initial render

Answer

When any state in the app changes

Question 4

What is the first argument to useReducer?

Accepted Answer

A reducer function (state, action) => newState

Answer

The initial state

Answer

The dispatch function

Answer

The action type

Question 5

What does useReducer return?

Accepted Answer

A [state, dispatch] tuple

Answer

Only the current state

Answer

Only the dispatch function

Answer

An object with state and actions

Question 6

When is useReducer generally preferred over useState?

Accepted Answer

When state transitions are complex or state depends on the previous value with multiple sub-values

Answer

For single boolean flags

Answer

When you want to avoid re-renders

Answer

When state is a string