40.White to move

In the position above Black has an advantage by one pawn.The question is

a)From your point of view is it enough for Black to use this advantage and lead to victory?

Thanks again to ,Eugene,Mr..... and Albin for sharing your thought to solve problem 39 by 1. Kc1 a3 2. Nc2+ Ka2 3. Nd4 Ka1 4. Kc2 Ka2 5. Ne2 Ka1 6. Nc1 a2 7. Nb3 mate.