Which one of the following is not a reserved keyword for C?

Which one of the following is not a reserved keyword for C?

2) Is the following statement a declaration or definition?
extern int i;

3) __________ is a graphical representation of a program.

4) Which one of the following is not a valid identifier?

5) Find the output of the following program.

void main()
  {
    int i=01289;
    printf("%d", i);
   }