I have some difficulties with a complexity proof : I work with 3 problems : A, B and C I know :A-> BA-> CC -> BA-> B meaning : if I have a yes answer  for A , then I have a yes answer for B. I know that A belongs to NP, B and C are NP-complete. Moreover I can write an algorithm for A with a quadratic number of calls to C.can I deduce something about the complexity of A?
np-complete proof, turing reduction
complexity theory;np complete;reductions;turing completeness