What is the difference between 'Undefined' and 'Null' in JavaScript?
A). Undefined is a value, while Null is an absence of value.
B). Undefined is an absence of value, while Null is a value.
C). Undefined is never intentional, while Null is always intentional.
D). Undefined is always intentional, while Null is never intentional.
What does the expression null == undefined return in JavaScript?
A). 1
B). 0
C). undefined
D). null
Which of the following is a valid use case for 'Null' in JavaScript?
A). Storing default values in variables.
B). Clearing or resetting object references.
C). Assigning placeholders in arrays.
D). Checking if a variable exists.
Which of the following statements is true regarding the behavior of 'Undefined' and 'Null' in JavaScript?
A). Undefined and Null are both falsy values in JavaScript.
B). Undefined and Null are both truthy values in JavaScript.
C). Undefined and Null have the same data type in JavaScript.
D). Undefined and Null cannot be compared in JavaScript.
How do you assign a variable to have a value of 'Null'?
A). Using the assignment operator =.
B). Using the null keyword.
C). Using the undefined keyword.
D). Using the void operator.
What happens when a function does not explicitly return a value in JavaScript?
A). It returns 'null'.
B). It returns 'undefined'.
C). It throws an error.
D). It returns 'object'.
How does the typeof operator behave when applied to an 'Undefined' value?
A). It returns 'undefined'.
B). It returns 'null'.
C). It throws an error.
D). It returns 'object'.
Which statement best describes the relationship between 'Undefined' and 'Null' in JavaScript?
A). Undefined and Null are interchangeable and can be used interchangeably in code.
B). Undefined and Null are distinct values representing different states in JavaScript.
C). Undefined is a subset of Null, encompassing all possible values of Null.
D). Null is a subset of Undefined, encompassing all possible values of Undefined.
What is the purpose of using 'Null' over 'Undefined' in certain programming scenarios?
A). To represent an intentional absence of value or object reference.
B). To assign default values to variables.
C). To represent uninitialized variables.
D). To check for variable existence.
How do you check if a variable has an 'Undefined' value in JavaScript?
A). Using the undefined keyword.
B). Using the null keyword.
C). Using the typeof operator.
D). Using the empty keyword.