P started from X at 10 a.m went towards town Y. Q started from Y at 12pm and went towards X. they met at 2 p.m. P reached his destination 20 minutes before Q did. At what time did Q reach his destination?
a) 4:20 p.m
b) 4:40 p.m
c) 5 p.m
d) 5:20 p.m