Which scenario describes a relationship of mutualism?

Responses

Oxpecker birds eat parasitic ticks off the backs of zebras.

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

A polar bear catches a seal for dinner.

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

The scenario that describes a relationship of mutualism is: Oxpecker birds eat parasitic ticks off the backs of zebras.