Which of the following statements best explains these relationships in terms of energy transfer?

Baker's yeast, Saccharomycetes cerevisiae, is the species of yeast that is commonly used in baking, brewing, and making wine. It is a single-celled organism; each cell is capable of undergoing asexual reproduction by mitosis and sexual reproduction by meiosis, forming spores that combine with other spores.
To find out if energy and nutritional resource availability determines which form of reproduction is used, researchers grew twenty yeast colonies on an agar medium plate providing ideal nutrient environments. Each colony was composed of a population of yeast that originated from a single yeast cell that had reproduced asexually to form a population of millions of yeast clones. That plate was used to produce replicate plates of yeast colonies. Each replicate plate was a mirror image of the original cultures, so each colony could be subjected to each treatment group. The replicate plates contained different media as follows.
Robust media: Contains all nutrients required by yeast in excess amounts
Complete media: Contains all nutrients at a level promoting exponential growth at rmax
Minimal media: Nutrients available at a low level, allowing growth, but stressing the yeast colonies
Deficient media: Nutrient content less than what is needed to sustain growth, extreme stress on yeast colonies
Eight replica plates were made, two plates of each media, and all plates were incubated at 30°C for 24 hours. Yeast from each colony were observed through a microscope and their means of reproduction determined. Table 1 summarizes these results.
Table 1: Reproductive Strategy of S. cerevisiae under different environmental stress levels (20 different colonies per medium ×2)

Sea otters living along the Pacific coast were hunted to near extinction in the nineteenth century. After being protected from hunting in the early 1900s, a remnant population of otters near Adak Island, Alaska, recovered rapidly. Otters did not return to the environmentally similar nearby island, Alaid Island. Sea otters eat sea urchins, which eat kelp, a brown alga. Researchers surveyed both islands in 1988, to measure sea urchin biomass and kelp density. The data are presented in Table 1.

Table 1. Kelp and sea urchin data from two Alaskan islands in 1988

In 1991, researchers at Adak Island observed the first attack by a killer whale on a sea otter in historical times. The researchers hypothesized that the population sizes of the larger marine mammals that the killer whales normally prey on declined, so the killer whales were starting to prey on different prey, including the smaller sea otters.

Which of the following best predicts the effects of an increase in killer whale predation on sea otters on the Adak Island ecosystem?

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