What is the result of the expression 5 + '5' in JavaScript?
A). 10
B). '55'
C). '10'
D). Error
What does the Symbol data type represent in JavaScript?
A). A unique identifier
B). A number
C). A boolean value
D). An object
What happens when you try to access a variable that has not been declared in JavaScript?
A). SyntaxError is thrown
B). ReferenceError is thrown
C). TypeError is thrown
D). Undefined
Which of the following statements about primitive values in JavaScript is true?
A). They are mutable
B). They are passed by reference
C). They are stored on the heap
D). They are immutable
Which primitive value represents absence of value or no value assigned?
A). undefined
B). null
C). 0
D). 'undefined'
What is the data type of the value undefined in JavaScript?
A). String
B). Object
C). Undefined
D). Number
What happens when you add two numbers using the + operator in JavaScript?
A). The numbers are concatenated
B). The numbers are multiplied
C). The numbers are added
D). An error occurs
What is the result of the expression true == 1 in JavaScript?
A). true
B). false
C). Error
D). 1
What is the default value of a variable in JavaScript if it is not initialized?
A). null
B). undefined
C). 0
D). 'undefined'
What is a primitive value in JavaScript?
A). A complex data structure
B). A basic data type
C). A function
D). An array