Differentiate between rank and taxon

A taxon is not an organism, but it’s rather any grouping one can distinguish. It is a taxonomic group or unit. A group of organisms that belongs together as per taxonomists. A taxon differs in sizes an example of big one is the beetles and a small one would be the giraffes.

Rank is simply the level of a taxon in the taxonomic heirarchy .

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.