Step-by-Step Solution
Key Concept: $\frac{x(e^x - 1)}{1 - \cos x} = \frac{e^x - 1}{x} \cdot \frac{x^2}{1 - \cos x} \to 1 \cdot \frac{x^2}{x^2/2} = 2$.
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Correct Answer: (3)