Scientists discover two hypothetical species of freshwater fish living in small pools that are connected by streams during the rainy season but isolated from each other during the dry season.
Species A reproduces asexually. Species B reproduces sexually. Both species are susceptible to a parasitic worm that causes a condition called "Black Spot Disease."
Scientists identified a pool in which both species of fish lived but in which no parasite existed. After taking an initial survey of both populations, scientists then intentionally infected the pool with the parasite that causes Black Spot Disease.
Three years later, they returned and resampled the populations of the two species of fish in the pool. Their results are represented in the graph below.
Which of the following statements is BEST supported by the results of this experiment?