Definition: 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'.
Input: Question: The carcinogenic action of Benzo (a) pyrene: 
 Options:  <1> It is due to the production of oxygen free radicals. <2> It is due to its biotransformation in a dihydrodiol. <3> It is due to its biotransformation in an epoxide. <4> It increases in tissues rich in epoxide hydrolase. <5> It diminishes in tissues rich in cytochrome P450.
