Step-by-step explanation:
Erwin Chargaff's research determined the composition of the nitrogen bases within a strand of DNA. His work determined that DNA composition varies, but the amount of adenine is always the same as thymine and the amount of cytosine is always the same as guanine. Chargaff also found that the composition of DNA varied from one species to another.
We can conclude that the correct answer is:
Answer:
the percent of adenine is equal to the percent of thymine and the percent of cytosine is equal to the percent of guanine.