Several lines of evidence suggest that Mars once was habitable, and the Panspermia hypothesis states that life originated on Earth when it came from Mars on a meteorite. Imagine you are the lucky chief biologist on the first mission to Mars and discover what appear to be fossilized cells. You dutifully perform chemical analysis of the fossil. Which of the following would suggest that these were NOT, in fact, fossilized cells but non-organic structures?

a. Absence of (cellular) nuclei
b. Existence of RNA monomers but not DNA
c. The presence of equal quantities of L- and D- amino acids.
d. An organized, regular appearance