The tick-bird is a species that sits on the back of large animals such as the rhinoceros. The bird eats the ticks and flies on the rhino, and so gets a free meal. The rhino gets the benefit of having those pesky bugs removed.

Which animal gets something useful from the other in this relationship?
A.
They both get something useful from each other.
B.
The rhino gets something useful from the tick-bird only.
C.
The tick-bird gets something useful from the rhino only.
D.
Neither of them gets anything useful from this relationship.

They both get something useful from each other.

Option: A

Explanation:

The rhinoceros enjoys relief from the insects, while the birds enjoy a meal. Thus, both help each other mutually.

Ox pecker birds also called tick birds,ride on huge African animals like rhinos and zebras that feed on external parasites like the bot-fly larvae and ticks. The ox peckers feast on the parasites they find, and they also lend the favor of raising a loud warning when a potential predator approaches. As the rhinos get relief from the insects, they allow these birds to sit on their backs.

Option A. They both get something useful from each other.

Explanation:

The symbiotic association in which both the organisms gets benefits from one another is called Mutualism. In rhino and tick-bird association,rhino provides food in the form of insects to the tick bird while tick bird feeds on the insects that are present on the rhino body which causes harm to the rhino. So both of them gets benefit.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.