With which one of the following statements concerning possible explanations for the latitudinal gradient in number of species would the author be most likely to agree? A. The time theory is the least plausible of proposed hypotheses, since it does not correctly assess the impact of ice ages upon tropical conditions. B. The rate-of-speciation hypothesis addresses a principal objection to the climatic-stability hypothesis. C. The major objection to the time theory is that it does not accurately reflect the degree to which the latitudinal gradient exists, especially when undiscovered species are taken into account. D. Despite the claims of the species-energy hypothesis, a high rate of biological growth and reproduction is more likely to exist with low biomass than with high biomass. E. An important advantage of the rate-of-speciation theory is that it considers species competition in a regional rather than local context.