Debt collectors acquiring location information from a third party must comply with multiple requirements: they must identify themselves and, if expressly asked, must identify their employer; they must state that the call is to confirm or correct location information; and once location information is received, they may not communicate with the third party again unless the person asks them to or they reasonably believe the earlier response was erroneous or incomplete and the person now has correct or complete location information. Therefore, all these conditions must be met, making option D the correct answer.