Task: Text Categorization
Input (English): Question: The carcinogenic action of Benzo (a) pyrene: 
 Options:  <0> It is due to the production of oxygen free radicals. <1> It is due to its biotransformation in a dihydrodiol. <2> It is due to its biotransformation in an epoxide. <3> It increases in tissues rich in epoxide hydrolase. <4> It diminishes in tissues rich in cytochrome P450.
Output (English): pharmacology