The correct answer is option A. When the company purchases office equipment for Rp.4,500,000.00 and pays Rp.1,500,000.00 in cash, the accounting equation is affected as follows: the office equipment asset increases by Rp.4,500,000.00, the cash asset decreases by Rp.1,500,000.00, and the liability (utang) increases by Rp.3,000,000.00. This is because the company has paid only a portion of the purchase price in cash and still owes the remaining amount.