Answer: Option 'C' is correct.
Step-by-step explanation:
Since we have given that
Annual gross profit of Sam's Swimming pool cleaning = $88400
So, Gross profit of Sam will be

Now, according to question, Sam charges $25 per week for each of his customers for 52 weeks .
So, Total amount he charges for each of his customers will be

So, Number of customers Sam's Swimming Pool Cleaning have is given by
Hence, Option 'C' is correct.