Subject: mathqa
Question: uncle bruce is baking chocolate chip cookies . he has 40 ounces of dough ( with no chocolate ) and 20 ounces of chocolate . how much chocolate is left over if he uses all the dough but only wants the cookies to consist of 25 % chocolate ?
Option: 
A: 6.5
B: 10.5
C: 6.7
D: 9.5
Answer: C