In a survey, a total of 500 surveys were filled out. One hundred of these responses had to be removed because of missing values for a particular question ("What is your gender?"). If 40 people indicated "Male" in response to this question, what was the valid percentage of "Male" responses?
A. 40%
B. 8%
C. 10%
D. 18%
E. 20%
Answer: C