What are two different forms of a single gene called?
a.
traits
b.
factors
c.
alleles < < <
d.
chromosomes
i think c

Alleles are two different forms of single gene that are located in specific position on a specific chromosome. It can be classified into two allele pairs: homozygous and heterozygous. In homozygous, both alleles are the same whether they are both dominant or recessive; while in heterozygous, one allele is dominant and the other is recessive.

C. Gene mutations only affect one gene while chromosome mutations affect many genes.

Explanation:

The difference is that the gene mutations only affect one gene while chromosome mutations affect many genes.