Task: Question Answering
Input (English): Question: Set S has a mean of 16 and a standard deviation of 1.5. We are going to add two additional numbers to Set S. Which pair of numbers would decrease the standard deviation the most?

 Option A: {2, 10}

 Option B: {9, 11}

 Option C: {16, 16}

 Option D: {10, 18}

 Option E: {7, 13}
Output (English): Option C