Question

1. 9. tiny one-celled creatures that can live outside the body?

a. virus
b. bacteria
c. fungi
d. parasites

Explanation:

To solve this, we analyze each option:

• a. Virus: Viruses are not cells; they are acellular and require a host to replicate, so they can't be considered one - celled creatures living outside the body in the same way as cellular organisms.
• b. Bacteria: Bacteria are single - celled (prokaryotic) organisms. They can survive and reproduce outside the human (or other) body, for example, in soil, water, or on surfaces.
• c. Fungi: While some fungi are single - celled (like yeasts), many are multicellular. Also, the description "tiny one - celled creatures" is more characteristic of bacteria in this context, and fungi generally have different ecological and physiological characteristics compared to the typical image of a tiny, single - celled, freely living (outside the body) microbe.
• d. Parasites: Parasites can be single - celled (like some protozoa) or multicellular (like worms). However, the term "parasite" implies a relationship with a host, and not all parasites are single - celled, and the description "tiny one - celled creatures that can live outside the body" is more specific to bacteria.

Answer:

b. Bacteria