Diamond is
the hardest mineral on the mohs scale
a no nonmetallic element
the only mineral with luster
an isotope of silicon

A would be correct. It’s the hardest mineral.

Although sickle cell mutations affect the shape of red blood cells but partial sickle cell anemia can provide an individual with resistance against malaria, in this case a mutation in one gene is affecting two phenotypic traits which indicates pleiotropy.