Consider the Pathway for the Synthesis of the Amino Acid

Multiple Choice

Consider the pathway for the synthesis of the amino acid arginine in Neurospora: Mutant strains of Neurospora are grown in minimal media supplements as follows.The strains may carry more than one mutation.Growth is shown by (+) and no growth is shown by (o) . Strain a accumulates citrulline, strain b does not.Indicate the statement that is most correct regarding these two strains.

A) Strain a has a mutation in ARG-E only.
B) Strain b has only one mutation.
C) Strain a has mutations in ARG-F and ARG-H.
D) Strain a has mutations in ARG-E, ARG-F and ARG-H.
E) Strain a has a mutation in ARG-H only.