In fruit flies, gray bodies (g) are dominant over black bodies (g), and red eyes (r) are dominant over orange eyes (r). each individual possesses two alleles for each trait. if a fly that is homozygous dominant for both traits is crossed with a fly that is homozygous recessive for both traits, what is the predicted genotype of the offspring?

The predicted genotype of the offspring is GgRr.

Explanation:

The gray body is dominant over black body. The genotype of gray body is GG and the genotype of black body is gg. Red eyes are dominant over orange eyes. The genotype for red eye is RR whereas the genotype of orange eye is rr.

GGRR is crossed with ggrr, the offspring produced by this cross is GgRr with gray body and red eyes.

GGRR  ×   ggrr

 GgRr.

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.