Which can be excluded due to the absence of fossil records A. the body of a jellyfish
B. the shell of a crab
C. a dinosaur's backbone
D. the shell of a snail

a. body of jellyfish

Explanation:

it is because they are made up of 95 percent of water and cannot be stored in rocks as fossil ...plz add my answer as brainliest

i believe that it is a exoplanet

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.