Question

which of the following is an example of a parasitic relationship between two organisms?
a tapeworms are segmented flatworms that attach themselves to the insides of the intestines of animals such as cows, pigs, and humans. they get food by eating the hosts partly digested food, depriving the host of nutrients.
b fleas harm their hosts, such as dogs, by biting their skin, suckling their blood, and causing them to itch. the fleas, in turn, get food and a warm home.
c some plants in the desert are able to produce harmful chemicals to kill and destroy other plants around it, to eliminate competition for resources.
d all of the above
e none of the above

Explanation:

• Option A: Tapeworms live in hosts' intestines, take nutrients (harm host), benefit themselves—parasitism.
• Option B: Fleas harm dogs (host) for food/home—parasitism.
• Option C: Plants kill competitors (resource competition, but also a form of negative interaction; however, the key is that in parasitism, one benefits at expense of host. The plant - plant interaction here is also a type of antagonistic relationship, and all these examples (A, B, C) represent parasitic or similar harmful - beneficial (for the parasite/competitor) relationships. So all above are examples of parasitic - like relationships.

Answer:

D. All of the above