In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Q: Question: One of the following compounds produces liver damage as the main toxic effect:
Options: <1> Diethylene glycol. <2> Methanol <3> Acetone. <4> Benzene. <5> Carbon tetrachloride.
A:
5