Final answer:
Depreciation expense decreases net income but does not affect the operating cash flow of a firm.
Step-by-step explanation:
The correct answer is option 1) Depreciation expense.
Depreciation expense is a non-cash expense that decreases net income but does not affect the operating cash flow of a firm. This is because depreciation is an accounting concept that allocates the cost of an asset over its useful life, rather than representing an actual outflow of cash.
For example, if a firm has a depreciation expense of $10,000 for the year, it reduces the firm's net income by $10,000. However, this depreciation expense does not require the firm to spend any cash. Therefore, it does not affect the firm's operating cash flow.