Subject: mathqa
Question: a total of 30 percent of the geese included in a certain migration study were male . if some of the geese migrated during the study and 25 percent of the migrating geese were male , what was the ratio of the migration rate for the male geese to the migration rate for the female geese ? [ migration rate for geese of a certain sex = ( number of geese of that sex migrating ) / ( total number of geese of that sex ) ]
Option: 
A: 7 / 12
B: 7 / 8
C: 9 / 7
D: 2 / 3
Answer: C