The modulus operator % in C only works with integers (int, long, etc.). It does not support floating-point types like float or double.

Why are (A) and (B) invalid?

(A) 2 % 4f; ❌

• 4f is a float value (4.0), and % cannot be used with float.
• This causes a compilation error.

(B) 2 % 4l; ❌

• 4l is a long integer, and 2 is also an integer.
• However, % supports long, so this is actually valid.

(C) Both 2 % 4f; and 2 % 4l; ❌

• Since 2 % 4l; is valid, this option is partially incorrect.
• But if 4l was mistakenly assumed as long double, then it would be invalid.

(D) 2 % 4; ✅ (Valid)

• Both 2 and 4 are integers, so % works fine.

Final Answer:

✅ (C) Both 2 % 4f; and 2 % 4l; (assuming 4l is mistakenly considered as long double).