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Combinatorics Difficulty 1.0 Junior Find the answer United Kingdom

A wooden fence consists of a series of vertical planks, each joined to the next vertical plank by four horizontal planks. The first and last planks in the fence are vertical. Which of the following could be the total number of planks in the fence?

(A) $96$ (B) $97$ (C) $98$ (D) $99$ (E) $100$

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