Which decision rule breaks ties when two efforts have equal cost of delay?

• A. Do the shortest job first
• B. Do the highest CoD first
• C. Do the most valuable first
• D. Do the lowest risk first

Answer: (A)

This question tests how to break ties in Weighted Shortest Job First (WSJF). The decision rule is to prioritize the shorter job when two efforts have the same cost of delay. WSJF is calculated as Cost of Delay divided by Job Size. If the Cost of Delay is equal for two options, the one with the smaller job size yields a larger WSJF score, meaning it delivers more value per unit of time and should be done first.

For example, if both efforts have a cost of delay of 50, but one requires 2 units of effort and the other 5, the WSJF values are 25 and 10 respectively. The shorter job first yields the higher WSJF and thus should be chosen first.

Other approaches—focusing on the highest cost of delay, the most valuable, or the lowest risk—don’t provide the same tie-breaker when CoD is equal, because they either ignore duration or prioritize different aspects rather than economic value per time unit.