Which statement executes a block only when a condition is true?

• A. For loop
• B. Output command
• C. If statement
• D. Case statement

Answer: (C)

Conditional execution is being tested here. An if statement runs its block only when the condition is true. It checks a boolean expression; if the result is true, the code inside executes, otherwise it’s skipped (you can add an else part to handle the false case). The other structures don’t fit this pattern: a for loop uses a condition to decide iteration count, not to decide a single block of code to run only when true; an output command just prints or displays something regardless of any condition; a case statement selects one of several blocks based on the value, not on a true/false test. So the if statement is the right choice.