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Function Fundamentals
Question 1
Which of the following is true about function declarations in JavaScript?
- A
They are not hoisted.
- B
They are hoisted to the top of their scope.
- C
They can be invoked only after they are defined.
- D
They cannot accept parameters.
Question 2
What happens if a function is declared inside another function?
- A
The inner function is accessible globally.
- B
The outer function gets overwritten by the inner function.
- C
The inner function is only accessible inside the outer function.
- D
Both functions are inaccessible.
Question 3
Which of the following is an example of method invocation?
- A
add(3, 5)
- B
new Person("Alex", 25)
- C
greet("John")
- D
user.greet()
Question 4
Which function invocation method is used to invoke a function and explicitly set the this value?
- A
apply()
- B
bind()
- C
call()
- D
Direct invocation
Question 5
What is the output of the following code?
const user = { name: "Alice" };
const greet = () => `Hello, ${this.name}!`;
console.log(greet.call(user));
- A
Hello, undefined!
- B
Hello, Alice!
- C
Hello, this.name!
- D
Error: Cannot read this
Question 6
What will be the output of this code?
const greet = () => {
return { name: "John" };
};
console.log(greet());
- A
{ name: "John" }
- B
undefined
- C
John
- D
Hello, undefined!
Question 7
Which of the following is NOT a valid way to declare a function in JavaScript?
- A
Function Declaration
- B
Function Expression
- C
Arrow Function
- D
Function Constructor
Question 8
What happens when a function expression is used in a callback?
- A
The function is executed immediately.
- B
The function is hoisted and executed before the callback.
- C
The function is executed once the event occurs.
- D
The callback is ignored.
Question 9
What will be the output of this code?
const greet = (name) => `Hello, ${name}`;
console.log(greet("Alice"));
- A
undefined
- B
Alice
- C
Hello, undefined
- D
Hello, Alice
Question 10
What will be the output of the following code?
const numbers = [1, 2, 3];
numbers.forEach(function(num) {
num = num * 2;
});
console.log(numbers);
- A
[1, 2, 3]
- B
[2, 4, 6]
- C
[1, 4, 9]
- D
[1, 2, 3, 6]
There are 10 questions to complete.