Answer:
Answer is D "Genes for the two traits are located close together on the same chromosome, and crossing over occurred between the two gene loci"
Step-by-step explanation:
Traits are distinguishing characteristics of an organism. The Phenotypic crossing of the Drosophila melanogaster specie with Gray body and long wings over that of the same specie but female with black body and apterous wings produced a total of 100 offspring, which showed a that genetic crossing were done on the closely related chromosomes of the body traits for the individual species.