CEMC Fermat, 2009

Combinatorics Difficulty 2.0 Junior Find the answer Canada

Sixty-four identical cubes are stacked in a $4 \times 4 \times 4$ arrangement and then some of the cubes are removed from the front as shown. No cube hidden from sight has been removed. How many cubes remain in the arrangement?

(A) $46$ (B) $40$ (C) $52$ (D) $55$ (E) $49$

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