The genomic DNA of an organism has a base composition of 40% C-G base pairs and 60% A-T base pairs. Assuming a random sequence of bases, what is the expected frequency of the TasI restriction sites 5'-AATT-3'

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.