According to the PMBOK Guide, specifically the Earned Value Management (EVM) section in the Control Costs process, we analyze project performance by comparing Earned Value (EV), Actual Cost (AC), and Planned Value (PV).
1. Cost Analysis (Efficiency and Variance):
* Cost Variance (CV) formula: $CV = EV - AC$
* Calculation: $100 - 120 = -20$
* Interpretation: A negative CV ($-20$) indicates that the project is over budget or experiencing a cost overrun. The project has spent 120 workdays of effort to achieve only 100 workdays ' worth of work.
2. Schedule Analysis (Efficiency and Variance):
* Schedule Variance (SV) formula: $SV = EV - PV$
* Calculation: $100 - 80 = +20$
* Interpretation: A positive SV ($+20$) indicates that the project is ahead of schedule.
Analysis of Options:
* A. There is a cost underrun: Incorrect. A cost underrun occurs when CV is positive (EV > AC).
* B. There is a cost overrun: Correct. As calculated, the project has spent more than the value of the work performed ($AC > EV$).
* C. The project may not meet the deadline: Incorrect. Based on the data, the project is ahead of schedule ($EV > PV$), meaning it is currently likely to meet or beat the deadline.
* D. The project is 20 days behind schedule: Incorrect. The project is actually 20 days ahead of schedule ($SV = +20$).