CEMC Pascal, 2009

Combinatorics Difficulty 2.0 Junior Find the answer Canada

In the diagram, any $\clubsuit$ may be moved to any unoccupied space. What is the smallest number of $\clubsuit$ 's that must be moved so that each row and each column contains three $\clubsuit$ 's?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

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