If your average score on your first six mathematics tests was 85 and your average score on your first seven mathematics tests was 87, then your score on the seventh test was ___ if ___.
a) 91, you scored 95 on the seventh test
b) 93, you scored 96 on the seventh test
c) 89, you scored 91 on the seventh test
d) 87, you scored 88 on the seventh test
