Multiple choice technology web technology

What is the output of the alert function for the below lines of code? var sum, Sum; sum = 0; alert(Sum);

  1. 0

  2. undefined

  3. Exception(0365): object undefined!

  4. Javascript error in the browser
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B Correct answer
Explanation

JavaScript is case-sensitive, so 'sum' and 'Sum' are two completely different variables. The code only assigns a value to 'sum', leaving 'Sum' uninitialized. When alert(Sum) is called, it outputs 'undefined' because the variable Sum was never assigned a value.

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