Which is a factor that can determine how drinking will affect a person?   a. how many other people are drinking the same drink   b. the time of day a person drinks   c. gender and size   d. whether the person is drinking during the week or on the weekend

It would be C, gender and size. Smaller people have higher blood alcohol concentration, which is how much alcohol is in the bloodstream, compared to larger people. Also, females reach higher blood alcohol concentration faster than males because they have less water in their bodies to dilute it and less enzymes to break it down. Hope this helps!