A researcher examined the fitness of a trait in a population and plotted the data below. Which of the following is a valid conclusion that can be drawn from these data?

A) Trait value B is the optimal trait value
B) Fitness is frequency-dependent
C) Disruptive selection is acting on trait value C
D) Kin selection explains why the fitness of trait value A is lower than the fitness of trait value C
E) Trait value C will increase in the population