Task: Text Categorization
Input (English): Question: The microbiocidal action of iodine and chlorine and many of its derivatives is due to: 
 Options:  <0> They are oxidizing agents. <1> They bind specifically to the active centers of the enzymes. <2> They bind specifically to ribosomal proteins. <3> They induce pores in the membranes. <4> They cause the dissolution of membrane phospholipids.
Output (English): biology