Answer: C- $85,671
Explanation: Stuart being a cash basis tax payer, reports all his income and deductions or payments for the period on actual cash paid during the year.
His tax report must contain only transactions paid for during the year and his report should not contain any receivable or payable for the year.
From the above question, Stuart Gross Income is:
Sales (Paid) - $84,357 + Sale of cardboard packaging to recycling company(Paid) -$1,314. Total Gross income = $85,671