Q: You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
Question: A certain characteristic in a large population has a distribution that is symmetric about the mean m. 60 percent of the distribution lies within one standard deviation d of the mean. If the shelf's average life is 7.2 years and the standard deviation is 2.8 years, what percent of the distribution has more than 10 years as a shelf's average life?

Option A: 10%

Option B: 12%

Option C: 14%

Option D: 15%

Option E: 17%
A:
Option D