Answer:
Cystic fibrosis (CF) is a genetic (inherited) disease that causes sticky, thick mucus to build up in organs, including the lungs and the digestive system. In people who have CF, thick mucus clogs the airways and makes it difficult to breathe.
C. Aa heterozygous is a capital letter with a lowercase letter
Answer: I believe the answer is B - Nucled Acids.
Hope this helps.