In Colorado subalpine meadows, non-native dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 6 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion- free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence, seed production) in the native species by attractive more pollinators to the mixed plots.
Which of the following, if true, mostly undermines the researchers' reasoning?
A: Bumblebees preferentially visit dandelions over larkspurs in mixed plots
B: In mixed plots, pollinators can transfer pollen from one species to another to augment seed production
C: If left unchecked, non-native species like dandelions quickly crowd out native species
D: Seed germination is a more reliable measure of a species' fitness than seed production
E: Soil disturbances can result in fewer blooms, and hence lower seed production

The degree and depth of the disturbance by compaction, as well as soil type, influences whether a remedy is possible or feasible, or whether the damage is permanent is referred to as Soil disturbance. Degree and extent of soil disturbance has a potentially greater effect on shallow or infertile soil than it does on deep or fertile soils. The presence of inert matter, seed of other crops, or weed seed; germination percentage; vigor; appearance; and freedom from disease are important aspects of seed quality. High-quality seed lots should meet minimum standards for each of these characteristics.