Which of the following is the correct way to declare an integer variable in C?

• int var;

• integer var;

• var int;

• int_var;

What does the #include preprocessor directive do in C?

• It includes the standard I/O library

• It defines standard input-output functions

• It starts the main function

• It declares variables

Which of the following is a valid comment in C?

• // This is a comment

• /* This is a comment */

• Both a and c

In C, the main() function:

• Must always return an integer

• It is optional

• Can return any data type

• Is executed at the end of the program

Which of the following correctly declares a constant in C?

• #define PI 3.14

• const PI = 3.14

• constant PI = 3.14

• Both a) and b)

The correct syntax to print "Hello, World!" in C is:

• printf("Hello, World!");

• print("Hello, World!");

• cout << "Hello, World!";

• echo "Hello, World!";

Which header file must be included to use the printf() and scanf() functions?

Which of the following is NOT a valid variable name in C?

• 1variable

• variable1

• _variable

• variable_1

Which of the following statements about C is TRUE?

• C is not case-sensitive and they have the same value.

• Each statement in C must end with a semicolon.

• Functions in C cannot return any values.

• Variable names in C can start with a digit or have a digit alone as identifiers.

Which of the following statements is true about the main function in C?

• It must always return void.

• It is where the program execution starts.

• It can only be defined once in a program.

• Both B and C.