Context: In a group of Channel catfish, some individuals have a brown body and others have a white body. In this group, the gene for the body color trait has two alleles. The allele B is for a brown body, and the allele b is for a white body.
A certain Channel catfish from this group has a brown body. This catfish has one allele for a brown body and one allele for a white body.
Based on this information, what is this Channel catfish's genotype for the body color gene?
A. Bb
B. a brown body
Determine the correct option from the provided choices and reply with its corresponding letter.
Answer: A