Ans (C)
LCM of 120 and 200 is 600.
Suppose 600kg meal for there.
Each Man taken him meal = 600/120 = 5kg
Each Child taken him meal = 600/200 = 3kg
150 children have taken their meals = 150*3 = 450kg
remaining meals = 600 - 450 = 150kg
Men have taken their meals = 150/5 = 30