The correct option is A). 126
Step-by-step explanation:
Total number of tax returns = 9
Number of tax returns to be selected for an audit = 4
This is based on the concept of combinations which states that :
If we need to select r objects from total of n objects , then total number of ways to select r objects is given by formula :
Therefore, number of ways of selecting 4 tax returns for audit out of 9 tax returns :
Hence, Number of ways an IRS auditor can select 4 of 9 tax returns for an audit = 126
So, the correct option is A). 126