A researcher is involved in the investigation of an individual's genetic abnormality. Which situation could the researcher most likely rule out as the genetic cause of a mutation? A. Loss of a cytosine–guanine base pair B. Formation of an adenine–uracil base pair C. Substitution of an adenine–thymine base pair for a cytosine–guanine base pair D. Insertion of an extra adenine–thymine base pair
