Wait... what was I going to say again?
Perl, 13 17 14 +1 = 15 bytes
/./?$;=$_:say$

+1 for the -n flag
(saved 4 bytes thanks to @Dada)
As long as the input is not equal to the carriage return, it stores the input in $;.  If it is equal to the carriage return, it prints what's already in $;.
This assumes that all input can be characterized as questions, even if grammatically, they are not such.