There are two groups of students in the sixth grade. There are 30 students in group A, and 50 students in group B. If, on a particular day, 20% of the students in group A forget their homework, and 12% of the students in group B forget their homework, then what percentage of the sixth graders forgot their homework?
A. 13%
B. 14%
C. 15%
D. 16%
E. 17%
A. 13%
B. 14%
C. 15%
D. 16%
E. 17%