What will be the output of the following C code?

Question

a) a = 5
b) a = 10
c) Compilation error
d) Runtime error
https://code.sololearn.com/c4FPGweA3Xm8/?ref=app

Answer 1

c

Answer 2

C) Compilation error

Answer 3

It's compilation error
Because you are changing value of a which is already defined in preprocessor using define preprocessor.
U can't change value of a variable if it is define in preprocessor using

#define a 1 //or any value

Answer 4

~ swim ~ it gives error I guess. Right?
Because it see B as an another macro