Right choice is (b) 0.8
Explanation: For limit state of strength, the load combination is 1.2(DL+LL+WL/EL), for limit state of serviceability, the load combination is 1.0DL+0.8LL+0.8WL/EL, where DL=Dead load, LL=imposed load, WL=wind load, EL=earthquake load.