Correct: B
C is based on the B programming language developed at Bell Labs.
Correct: Dennis Ritchie
Dennis Ritchie developed C at Bell Labs in the 1970s.
Correct: .c
C programs are saved with `.c` extension.
Correct: int
`int` is a valid data type keyword in C.
Correct: Middle
C is considered a middle-level language because it supports both high- and low-level programming.
Correct: 1972
C was developed in 1972 by Dennis Ritchie.
Correct: System programming
C is heavily used for system-level programming like OS, compilers, etc.
Correct: Both TurboC and GCC
TurboC and GCC are both compilers for C.
Correct: main()
The standard form is `int main()` or `void main()`.
Correct: Compiler
C uses a compiler to convert code to machine language.