Explanation
1. Identify the "Colors" (Holes):
There are only 2 colors available in the drawer:
2. Analyze the Worst-Case Scenario:
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If you pick 1 sock, it could be either black or brown.
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If you pick 2 socks, the worst-case is that you get one of each color (1 Black and 1 Brown). In this case, you do not have a pair yet.
3. The Deciding Pick:
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When you pick the 3rd sock, it must be either black or brown.
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If it is Black, it forms a pair with the first black sock.
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If it is Brown, it forms a pair with the first brown sock.
Mathematical Representation:
If there are n colors, the minimum number of items k required to ensure at least one pair is:
In this case, n=2 (Black and Brown):
Even though there are 20 socks in total, you only need to pick 3 to guarantee a matching pair.
Correct Option: (c) 3
