Understanding Evolution : Personal response question

1

Understanding Evolution Personal response
question
A class of 100 students was tested for the
ability to taste phenylthiocarbamide (PTC). It
was found that 50 students could taste it very
strongly (genotype TT), 20 students could taste
it weakly (genotype Tt), and 30 students could
not taste PTC at all (genotype tt). What is the
frequency of the recessive allele, t, in the
population?
a. 0.40 b. 0.50 c. 0.60 d. 0.80