Task: Question Answering
Input (English): Question: Ketogenic amino acids: 
 Options:  <1> They may contribute to the synthesis of glucose. <2> They are intermediaries of the urea cycle. <3> They are the substrate of reactions catalyzed by transketolase. <4> They can produce acetyl-coenzyme A. <5> They are eliminated in the form of ketoses.
Output (English): 4