Which statement is true regarding the use of 'Undefined'?
A). Undefined is commonly used to reset variables in loops.
B). Undefined is generally avoided and considered a programming error.
C). Undefined is used to represent empty strings.
D). Undefined is only used in function declarations.
What does the expression null == undefined return in JavaScript?
A). 1
B). 0
C). undefined
D). null
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 of the following scenarios is a common cause of variables having an 'Undefined' value?
A). When variables are explicitly set to 'Undefined'.
B). When variables are declared but not initialized.
C). When variables are intentionally set to 'Null'.
D). When variables are assigned default values.
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.
Which of the following is an example of using 'Null' in JavaScript?
A). let user = null;
B). let user = undefined;
C). let user;
D). let user = '';
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.
When does the JavaScript engine assign an 'Undefined' value to a variable?
A). When the variable is intentionally set to 'Undefined'.
B). When the variable is not declared but used.
C). When the variable is declared but not initialized.
D). When the variable is initialized with the value '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.
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.