They would know if they see anything like traces of water or anything else that would be nessecary for a living organism to have. They look for these with technology like the hubble telescope as well as the drone on Mars to gather as much information as possible.
The answer is class and family.
<span>Taxonomic groups are used for biological classification. There are eight main taxonomic groups: domain, kingdom, phylum, class, order, family, genus and species, with the domain as the most inclusive and species as the least inclusive. If we take a look on Mammalia and Hominidae classification, we can assume that Mammalia represents class, and Hominidae represents family:</span>
<span>1. Domain: Eukarya</span>
<span>2. Kingdom: Animalia</span>
<span>3. Phylum: Chordata</span>
<span><u>4. Class: Mammalia</u></span>
<span>5. Order: Primates</span>
<span><u>6. Family: Hominidae</u></span>
<span>7. Genus: Homo</span>
<span>8. Species: Homo sapiens</span>
Nerves are cells that can detect any type of pressure, movement, or anything of that nature. If we didn't have nerves, we couldn't feel pain. If the nerves in a foot are damaged, you wouldn't feel the pain of it being burned.
Answer:
A. Deposition - sediment is set down in a new place
5. System level
6. Organ level