Which type of relationship exists between two whales that both feed on tuna?

a. predation
b. parasitism
c. competition
d. commensalism

I believe the correct answer is:

C. competition

The correct answer is C. There is a relationship of competition between two whales that both feed on tuna.

Explanation:

In biology, competition refers to any antagonistic relationship associated with the struggle for existence, for dominance, for food, space and other resources between organisms, species or populations of species that need the same resources.

This "competition" often involves associations of organisms, species or entire guilds, as well as complex phenomena of bioconstruction, symbiosis and mutualism. Regulatory systems by auto-inhibition or predation of competition make the coexistence of many species possible, even in very poor environments (oligotrophs) which are often the richest in biodiversity.