Answer & Solution
Answer: Option a
Solution:
When a variable is declared but not initialized, its type is undefined in JavaScript. The correct option is a. Undefined.
Q
What is the outcome of console.log(typeof x); if x is declared but not initialized in JavaScript?
Related Questions on Average
Which of the following statements is true about the let keyword in JavaScript?
A). a. Variables declared with let have global scope
B). b. Variables declared with let are block-scoped
C). c. let is used to declare constants
D). d. let is used to declare functions
Which of the following statements is true about the let keyword in JavaScript?
A). a. Variables declared with let have global scope
B). b. Variables declared with let are block-scoped
C). c. let is used to declare constants
D). d. let is used to declare functions
What is the outcome of console.log(typeof x); if x is declared but not initialized in JavaScript?
A). a. Undefined
B). b. Null
C). c. Error
D). d. Object
Which keyword is used to declare a variable that cannot be reassigned in JavaScript?
A). a. var
B). b. let
C). c. const
D). d. mutable
What is the purpose of using the const keyword in JavaScript?
A). a. To declare variables with function scope
B). b. To declare variables with block scope
C). c. To declare constants with immutable values
D). d. To declare objects in JavaScript
What will happen if you try to reassign a value to a constant declared with const in JavaScript?
A). a. It will throw an error
B). b. It will silently ignore the assignment
C). c. It will convert the variable to let
D). d. It will convert the variable to var
What will happen if you try to reassign a value to a constant declared with const in JavaScript?
A). a. It will throw an error
B). b. It will silently ignore the assignment
C). c. It will convert the variable to let
D). d. It will convert the variable to var
Which keyword is used to declare a variable that cannot be reassigned in JavaScript?
A). a. var
B). b. let
C). c. const
D). d. mutable
Which of the following variable names is valid in JavaScript?
A). a. my variable
B). b. _variable
C). c. 3variable
D). d. variable$
What will console.log(a); output if a is declared outside a function but inside a block using let in JavaScript?
A). a. It will output the value of a
B). b. It will throw an error
C). c. It will output undefined
D). d. It