Question

Assume we have 25 mL of a 2.5 M HCl and a solution of NaOH of unkown concentration. The two react via the following equation.

Answer 1

Answer is  A - HCl is the titrant and D-NaOH is the analyte.

In a titration process, the solution of unknown concentration considered is the analyte. During titration, a standard solution(titrant) is added to an analyte until the equivalence point is achieved.

So in this case as the concentration of NaOH is not known,NaOH is the analyte.

Titrant is the solution whose concentration  is known to us and is added to an analyte until the equivalence point is reached. In this case since we know the concentration of HCl, HCl is the titrant.