Kimberly is 7 years old. She asks her mother to buy her clothes at the start of the new academic year. However, her mother tells her that she won't buy too many clothes now as Kimberly will grow them out soon. She expects Kimberly, on an average, to gain ________ pounds per year during middle and late childhood.
A) 1 to 2
B) 2 to 3
C) 5 to 7
D) 7 to 10