Answer:
They get energy from their host
Explanation:
Literally, parasites are those organisms that when, in a relationship with another organisms (called hosts), they do not benefit the hosts.
This implies that, the parasite get food and energy from their hosts, however, the hosts get nothing in return. except from being harm by the parasites.
It should be noted that parasites are not limited to animals only; A parasite can be an animal, plant, and they can also be insects, etc.
