Context: In a group of rose plants, some individuals have thorns and others do not. In this group, the gene for the thorns trait has two alleles. The allele R is for having thorns, and the allele r is for not having thorns.
A certain rose plant from this group does not have thorns. This plant has two alleles for not having thorns.
Based on this information, what is this rose plant's phenotype for the thorns trait?
A. rr
B. not having thorns
Pick the correct answer from the listed options and provide the letter of the selected option.
Answer: B