A company makes round parts for a machine. The parts must have a diameter reasonably close to the target diameter or they will be rejected. If the target mean diameter is 10 mm with a standard deviation of 0.05 mm, what are the smallest and largest diameters allowed if 99.7% will be accepted? Assume the part diameters are normally distributed.

A. 9.85 mm and 10.15 mm
B. 9.9 mm and 10.1 mm
C. 9.85 mm and 10.1 mm
D. 9.9 mm and 10.15 mm