Context: In a group of rabbits, some individuals have black fur and others have brown fur. In this group, the gene for the fur color trait has two alleles. The allele F is for black fur, and the allele f is for brown fur.
Gumdrop, a rabbit from this group, has brown fur. Gumdrop has two alleles for brown fur.
Based on this information, what is Gumdrop's phenotype for the fur color trait?
A. ff
B. brown fur
Choose the right answer from the options and respond with its letter.

B