A hypothetical three step metabolic pathway consists of intermediates W, X, Y AND Z and exzymes A, B, AND C. Assume the order of the enzymatic steps in the pathway from the subsequent information:
1. Compound Q a metabolic inhibitor of enzyme B causes Z to build up
2. A mutant in enzyme C needs Y for growth.
3. An inhibitor of enzyme A causes W, Y and Z to accumulate
4. Compound P a metabolic inhibitor of enzyme C, causes W and Z to build up