(A). You have at least one copy of the dominant allele T
Explanation:
Tongue rolling is the capability of individual to roll the tongue upwards in a tube-like structure. The muscles in the tongue allow this rolling movement.
Tongue rolling is related with genetic inheritance. Different genotype determines rolling of tongue. Individual with dominant allele(T) either heterozygous dominant(Tt) alleles or homozygous dominant(TT) alleles shows the tongue rolling trait. The homozygous recessive genotype will not show tongue rolling trait. So, tongue rolling trait is determined by a dominant allele.
