Final answer:
Bateman's Principle is the concept that the sex with the steeper relation between reproductive success and mating success experiences stronger sexual selection, often leading to pronounced secondary sexual characteristics like the peacock's tail.
Step-by-step explanation:
The correct choice for Bateman's Principle is C) Whichever sex has the steeper relationship between reproductive success and mating success will be the sex in which sexual selection is stronger. This principle is a cornerstone of sexual selection theory and explains why traits that may seem negative for survival can actually promote reproductive success.
In many species, males exhibit traits such as colorful plumage or perform elaborate courtship displays. While these traits may not aid in survival, and can sometimes even be detrimental, they are important for attracting mates and maximizing reproductive success. The good genes hypothesis also plays a role here, suggesting that females choose mates with impressive traits to ensure the propagation of superior genes to their offspring. Bateman's Principle helps explain the evolution of these seemingly paradoxical traits through the lens of reproductive advantage.