Answer:
False
Step-by-step explanation:
Although scenario analysis is a way of testing forecasts but not necessarily one assumption at a time.
Scenario analysis is done by keeping all the key risks in mind and predicting the possible outcomes, primary effects and secondary effects on a project. Secondary effects are further analysed to see if there are any other possible risks to consider.
It is not compulsory to change just one attribute at a time, many factors are alone and together analysed to predict better and have a proper set of actions ready to tackle the crisis.