Which term describes a physical structure that allows the organism to survive in its particular environment?
a. population
b. ecosystem
c. adaptation
d. evolution

The answer is c. Adaptation

Adaptation is a physical characteristic that helps an organism survive in an environment.  This help them survive in a natural selections.

The examples are :
- cactus that evolved to change its body structure to retain as much water as possible

- Bat that have adapted their hearing to hunt at night

Ribonuclease activity is a type of nuclease that catalyzes the degradation of rna into small components.