Hi, this could be our analysis of the passage: 1) introduce a phenomenon (more species in the tropics - middle latitudes). 2) propose three hypotheses which they end up rejecting (time theory, species-energy hypothesis, climatic stability) 3) introduce and defend a fourth hypothesis, the rate-of-speciation hypothesis.
This question is specifically asking about the second hypothesis, the species-energy hypothesis. What does this hypothesis say? That "energy from the Sun correlate[s] with rates of growth and reproduction"... and that "greater energy influx lead[s] to bigger populations, thereby lowering the probability of local extinction". In brief, that more energy input means more populations and speciation.
A) We're not considered with agricultural tracts. B) The discussion of death rates was in the author's contradiction to the species-energy hypothesis, not the hypothesis itself. C) We don't know too much about the relationship between number of individual organisms and number of species. Remember that the main point is that more energy input - more species. D) Don't know too much about death rates in high-energy areas. E) This checks out. When there is low energy input, there's a slow rate of growth and reproduction. This is almost verbatim from lines 18-21. Note that we know arctic tundra are low energy areas because the theory says low energy areas have less species and the whole point of the theory is to explain why there are few species at high latitudes (arctic area). Therefore, the hypothesis implies arctic tundra is a low energy area.