Which primitive data type represents unique identifiers introduced in ECMAScript 6?
A). Number
B). Symbol
C). Boolean
D). Undefined
Which data type represents variables that have been explicitly set to have no value?
A). Number
B). Undefined
C). String
D). Null
How is the Symbol data type different from other primitive data types in JavaScript?
A). Symbols can be used as object keys
B). Symbols can be compared directly
C). Symbols can be used in mathematical operations
D). Symbols can be concatenated with strings
Which primitive data type represents variables that have been explicitly set to represent no value?
A). Number
B). String
C). Undefined
D). Null
Which of the following statements accurately describes the Boolean data type in JavaScript?
A). It represents textual data
B). It represents numeric data
C). It represents logical values
D). It represents an absence of value
What does the expression typeof 42 return in JavaScript?
A). number
B). string
C). undefined
D). boolean
What is the result of the expression typeof undefined in JavaScript?
A). number
B). string
C). undefined
D). boolean
Which data type is represented by the value null in JavaScript?
A). Numeric data
B). Textual data
C). Absence of value
D). Logical value
Which primitive data type represents textual data?
A). Number
B). String
C). Boolean
D). Undefined
How is the Undefined data type different from the Null data type in JavaScript?
A). Undefined represents an intentional absence of value
B). Null represents variables not initialized
C). Undefined is used for object keys
D). Null is used for mathematical operations