Re-phrased answer:-
2) Which of the following is true? QNH is:
a. Always more than 1013.25 hPa
b. Always less than 1013.25 hPa
c. QNH can be lower as well as higher than 1013.25 hPa
d. Can never be above or below 1013 hPa
Voilą that is the answer to your next question. Flight levels are wrt 1013.25. Local pressure altitude wrt to QNH is not given and as QNH can be lower as well as higher than 1013.25 hPa. Thus, d. Nothing, insufficient information