What is the main purpose of the () operator in JavaScript functions?

How do you define and invoke a function to calculate the square of a number in one step?

A). var square = function(n) { return n * n; }; square(5);

B). (function(n) { return n * n; })(5);

C). function square(n) { return n * n; } square(5);

D). var square = (n) { return n * n; }; square(5);

What does return do inside a function?

A). Stops the function

B). Returns a value to the caller

C). Both A and B

D). Declares a variable

Which of these is the correct way to define and immediately invoke a function?

A). function() { return 1; };

B). (function() { return 1; })();

C). function() { return 1; }();

D). function {}()

How can you invoke a function using the call method?

A). myFunction.call();

B). myFunction.call(this);

C). call.myFunction();

D). call(myFunction);

What does return without a value return?

A). 0

B). null

C). undefined

D). NaN

What happens if a function is invoked without parentheses in an event handler like onclick='myFunction'?

A). The function is executed immediately

B). The function reference is assigned

C). An error is thrown

D). The function does not work

What is the output of function sum(a, b) { return a + b; } console.log(sum(3, 4));?

A). 34

B). 7

C). undefined

D). sum

Which of the following is an example of an Immediately Invoked Function Expression (IIFE)?

A). function() {}();

B). (function() {})();

C). function() {}

D). (function {})();

What is the output of function sayHi() { return 'Hi'; } alert(sayHi());?

A). sayHi

B). Hi

C). undefined

D). alert

How do you invoke a method named greet on an object person?

A). person.greet;

B). person.greet();

C). greet(person);

D). persongreet;