GMAT Math

Grocer stacked oranges in a pile. Bottom layer was rectangular with 3 rows of 5 oranges each. In 2nd layer, from bottom, each orange rested on 4 oranges from bottom layer and in the 3rd layer each orange rested on 4 oranges from 2nd layer. Which of the following is max number of oranges that could have been in 3rd layer?
A) 5
B) 4
C) 3
D) 2
E) 1

Bottom layer:

:):):):)

:):):):)

:):):):)

Second layer on top of first layer:

:):):):)
_:):):):)_
:):):):)
_:):):):)_
:):):):)

Third layer on top of second layer:

:):):)
_:):):)_
:):):)

Choose C.