Task: Question Answering
Input (English): Question: Bortezomib is a proteasome inhibitor approved to treat multiple myeloma. What type of acid group is present in its structure and is necessary for its activity ?: 
 Options:  <1> Boronic. <2> Phosphonic <3> Sulfinic <4> Carb <5> Carboxylic
Output (English): 1