If a Mutagenesis Screen Provides Some Number of Alleles Shown

If a mutagenesis screen provides some number of alleles shown by complementation analysis to be in the same gene, which of the following is true?

A) These mutants can be used to identify the role of the gene in metabolism.
B) The gene being studied must be present in more than one copy per haploid genome.
C) The gene, in whole or in part, must be involved in transformation.
D) The gene must be highly conserved in evolution.
E) The gene must be involved in regulating a signal pathway.