I don't think this is a Gabriel synthesis since an alkyl halide isn't being turned into an amine, but regardless this is pretty advanced for the DAT.
You could deduce the answer by knowing that an acid is created, so one of the answers is carboxylic acid, so D is out. Then the other choices differ in an amide, ketone, and aldehyde. I'd just guess amide because two moles of NH3 reacted with a carboxylic acid, probably leading to an amide.