護理師在協助病人取得知情同意時，應採取下列哪項行動？

Core concept: Informed consent embodies client autonomy and ensures that the client makes a medical decision voluntarily after being fully informed. The nurse plays an important role in this process but within clearly defined boundaries. Why the correct answer is correct: Option B focuses on confirming the client's willingness (voluntariness) and capacity (mental competence), which is the key step the nurse must verify before the document is signed. Ensuring that the signing process is free and uncoerced, and that the client has the capacity to understand the relevant information, is the nurse's legal and ethical responsibility. Why the other options are incorrect: Options D and A describe information that is important within the informed consent process, but the primary person responsible for explaining this information is the physician who performs the procedure. The nurse's role is to assist the physician in confirming that the client has received this information, not to provide detailed medical explanations independently, which could exceed the nurse's scope of practice or create confusion. Although the nurse may clarify terminology (option C), this is not the primary or most central action; verifying the client's willingness and capacity is a more fundamental and important step. Clinical reasoning (Priority / Safety): During the informed consent process, the client's autonomy and medical safety are the highest principles. The nurse's primary task is to ensure that the client can make a truly autonomous decision, which depends on freedom from coercion and the capacity to decide. If the client's willingness is coerced or capacity is impaired, any further explanation of information becomes meaningless.