Which of the following describes a relationship of mutualilism?

A. Oxpecker birds eat parasitic ticks off the backs of zebras.

B. Birds feed off the insects that are stirred up from the grasses as cattle move through.

C. A polar bear catches a seal for dinner.

D. A tapeworm latches itself in the intestines of a rat, feeding off all the nutrients eaten by the rat.

Option A. Oxpecker birds eat parasitic ticks off the backs of zebras, is the correct statement for Mutualism.

Explanation:

Oxpecker birds is a special type of bird which feed on the parasites that are present on the surface of zebra. These parasites causes harm to the zebra. Oxpecker birds free the zebra from the parasite while the zebra provides food to the oxpecker bird and both get benefit from each other. So it is Mutualism relationship.

Option D. A tapeworm latches itself in the intestines of a rat, feeding off all the nutrients eaten by the rat, is a type of parasitism relationship.