Answer:
d. cash receipts from sales of investments.
Step-by-step explanation:
The cash flow statement categories the company's transactions in a financial period into 3 groups; these are operating, investing and financing.
The net profit/loss, depreciation, changes in current assets (other than cash) and liabilities are considered as operating activities including income taxes.
The sale of assets, purchase/sale of investments are examples of investing activities while the issuance of stocks, debt principal deduction (loan settlement), issuance of debt securities etc are examples of financing activities.
As such, option d. cash receipts from sales of investments is an investing activity.