The dropdowns for a and b says "A, B, or C" for both of them

Three activities are candidates for crashing on a project network for a large computer installation (all are, of course, critical). Activity details are in the following table: Activity Normal Time Crash Time (days) (days) 7 6 4 2 11 9 A B Normal Cost $4.500 $1.200 $4,000 Total Cost with Immediate Crashing Predecessor(s) $5,000 $3,100 $6,400 B a) Activity that should be crashed first to reduce the project duration by 1 day is b) Activity that should be crashed next to reduce the project duration by one additional day is c) Total cost of crashing the project by 2 days = $(Enter your response as an integer.)