The most important feature of the series of tennis lessons were the large number of strokes taught?

1. A Option A: The most important feature of the series of tennis lessons were the large number of strokes taught.
2. B Option B: The most important feature of the series of tennis lessons was the large amount of strokes taught.
3. C Option C: The most important feature of the series of tennis lessons was the largeness of the amount of strokes taught.
4. D Option D: The most important feature of the series of tennis lessons was the large number of strokes taught.

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