B. The argument is invalid because the conclusion does not follow the premises.
Step-by-step explanation:
It is given △ABC and △QRS are congruent.In congruent triangles corresponding sides and angles are equal.
Thus the conclusion The corresponding angles of △ABC and △QRS are not congruent is not a valid statement.
If the triangles are congruent then the conclusion reached is not following the given statement .Hence The argument is invalid because the conclusion does not follow the premises.