Four children randomly line up, single file. What is the probability that they are in height order, with the shortest child in front? All of the children are of different heights. A 1/4
B 1/256
C 1/16
D 1/24

the answer is D.  1/24

Step-by-step explanation:

The number of ways for the children to line up is 4!=4×3×2×1=24 -- there are 4 choices for who is first in line, then 3 for who is second, etc. Only one of these lines has the children in the order specified.

72 is the answer to this problem