Which of the following is not a valid control structure in C?if-elseforswitchselect

To determine which of the following is not a valid control structure in C, let’s analyze each option:

1. if-else: This is a valid control structure used for conditional execution based on a true/false condition.

2. for: This is a valid control structure used for looping a specific number of times.

3. switch: This is a valid control structure used for executing one block of code among multiple options based on the value of a variable.

4. select: This is not a valid control structure in standard C. The select statement is used in some other programming languages (like SQL) or in systems programming (such as in UNIX for I/O multiplexing), but it does not exist as a control structure in the C programming language.

Final Answer

select is not a valid control structure in C.