In the statement of cash flows, depreciation and amortization expense is added back to net income because:

(a) the cash disbursements for these accrued expenses will be made in a future period.
(b) these expenses do not affect cash, but were subtracted in the determination of net income.
(c) these expenses are recognized for accounting purposes, but they do not represent economic costs.
(d) these expenses affect investing activities, not operating activities.