Q: Anemia, leukemia, hemophilia, and sickle-cell disease are examples of conditions that primarily affect what?


Read this paragraph and choose the correct option from the provided answers:

Some diseases affect mainly the blood or its components. They include anemia, leukemia, hemophilia, and sickle-cell disease.

 Choices:

- Lungs

- brain

- heart

- blood


A:
blood