When one nucleotide contains cytosine, what type of base is the cytosine attached to on the opposite nucleotide strand?

guanine bases on the opposite strand.

Explanation:

adenine = the same amount of thymine vise versa

cytosine = the same amount of  guanine

true                                                                                                       true true true true true true

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.