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.
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'.
How is 'Null' different from 'Undefined'?
A). Null represents variables that have been initialized but not declared.
B). Null represents an intentional absence of value or object reference.
C). Null is never used in programming.
D). Null is a substitute for 'Undefined'.
What does the expression typeof null return in JavaScript?
A). null
B). object
C). undefined
D). function
Which of the following statements is correct regarding the comparison of 'Undefined' and 'Null'?
A). Undefined and Null are strictly equal in JavaScript.
B). Undefined and Null are not strictly equal in JavaScript.
C). Undefined is considered a subtype of Null.
D). Null is considered a subtype of Undefined.
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.
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 is the result of the expression typeof undefinedVariable if undefinedVariable is not declared?
A). object
B). function
C). undefined
D). null
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.
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'.