The height of males aged between 17 and 20 follows a normal distribution, with a mean of 71.1 inches and a standard deviation of 2.3 inches.
If the number of males between ages 17 and 20 is 11.0 million, how many males in this age group have heights between 69 inches and 73 inches?

A)3.6 million
B)4.1 million
C)6.8 million
D)9.7 million