The density of mars is 3.93 g/cm3
The simple organisms may be unicellular, consisting of just 1 cell, but more complex organisms are multi-cellular, which means they might have more than one. So the answer you are looking for is A. 1
I hope this helps! :>
Anticodons are a part of transfer RNA(tRNA) molecules, and corresponds to a codon on a messenger RNA(mRNA) molecule.
Your answer is A, anticodon; codon.