A Strain That Can Grow in a Minimal Medium Containing

A strain that can grow in a minimal medium containing arginine, but NOT in a minimal medium containing citrulline or ornithine would have a mutation in the gene that encodes for Bread mold can grow in a minimal medium without supplements (wild type) while certain mutated strains (mutants) can only grow in a minimal medium that is supplemented with specific intermediates found in the following metabolic pathway for arginine synthesis:
minimal ------> ornithine -------> citrulline ------> arginine, where enzyme 1 converts the precursor to ornithine, enzyme 2 converts ornithine to citrulline, and enzyme 3 converts citrulline to arginine.

A) enzyme 1.
B) enzyme 2.
C) enzyme 3.
D) both enzymes 1 and 3.
E) both enzymes 2 and 3.