Which loop structure guarantees execution of the loop body at least once?
- for
- while
- do-while
- foreach
Answer: do-while
do-while loop checks condition AFTER executing the body, ensuring at least one iteration. Syntax: do { ... } while(condition);. Useful for menu-driven programs, input validation where first attempt is always needed. while/for check condition BEFORE execution, potentially skipping body entirely if condition initially false.