In Calculating the Time-Cost Trade-Off Combinations for a Project's Crash

In calculating the time-cost trade-off combinations for a project's crash options,the slope for each activity is given by ______.

A) the ratio of the (crash cost less normal cost) to (normal time less crash time)
B) the ratio of the (normal time less crash time) to (crash cost less normal cost)
C) the product of the (crash cost less normal cost) and (normal time less crash time)
D) the sum of (crash cost less normal cost) and (normal time less crash time)