[c] How can I print a quotation mark in C?

Without a backslash, special characters have a natural special meaning. With a backslash they print as they appear.

\   -   escape the next character
"   -   start or end of string
’   -   start or end a character constant
%   -   start a format specification
\\  -   print a backslash
\"  -   print a double quote
\’  -   print a single quote
%%  -   print a percent sign

The statement

printf("  \"  "); 

will print you the quotes. You can also print these special characters \a, \b, \f, \n, \r, \t and \v with a (slash) preceeding it.