Task: Text Categorization
Input (English): Question: COMPLETE: in the Krebs cycle 4 oxidation reactions occur, in 3 of them the final acceptor electron is ___ and in the other is ___: 
 Options:  <0> FAD / FMN. <1> NAD + / FMN. <2> NADP + / FAD. <3> NAD + / FAD. <4> FAD / NAD +.
Output (English): chemistry