You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Which immune system function is carried out by antibodies?   
 (A) Antibodies produce proteins that attach to an invading virus. (B) Antibodies attach to an invading virus as a target marker. (C) Antibodies engulf the invading virus as a defense mechanism. (D) Antibodies release enzymes that lyse the invading virus.
B