stack of oranges

[chacha0212]

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

[MartyMurray]

Bottom layer:

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Second layer on top of first layer:

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Third layer on top of second layer:

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Choose C.