Candidate move

In this difficult position the second player Gata Kamsy went for 30...N8e7, whereupon he had to continue suffering and could save the game only by a miracle. How would be your assessment of the alternative 30...Nxd4 31.Bxd4 Bxa2 with a discovered attack on the the white bishop d4?
A) good enough for equality;
B) still worse for Black, but better than the game anyway;
C) a direct way to disaster, White wins immediately.