What is the primary difference between a while statement and a do while statement?

• A. A while checks after executing the loop
• B. A do while checks before executing the loop
• C. A do while guarantees execution at least once
• D. A while guarantees execution at least once

Answer: (C)

The primary difference between a while statement and a do while statement lies in when the condition is evaluated and how it affects loop execution. A while loop evaluates its condition before executing the loop body. This means that if the condition is false at the outset, the body of the loop may never execute at all.

In contrast, a do while loop guarantees that the loop body is executed at least once, regardless of whether the condition is true or false at the time of evaluation. This is because the condition in a do while is checked after the execution of the loop body. Thus, even if the condition is false, the loop will still run once before the condition check occurs.

Understanding this distinction is crucial in scenarios where you want to ensure that a block of code within the loop executes at least one time, which is why the choice indicating that a do while guarantees execution at least once is accurate.