Which of the following is an example of commensalism? a) birds feed off the insects that are stirred up from the grasses as cattle move through. b) a polar bear catches a seal for dinner. c) a tapeworm latches itself in the intestines of a rat, feeding off all the nutrient eaten by the rat. d) oxpecker birds eat parasitic ticks off the backs of zebras.

Commensalism is the relation ship between two species where one of the species is being benefited while the other is not benefited and not even harmed.

It is a type of symbiosis

the correct answer is

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

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

po-215 i got it right on the quiz