Heredity is best described as a. the single-most important influence on skill-related fitness b. natural ablities that cannot be changed c. highly mutable personal characteristics d. none of the above

The right option is; B. natural abilities that cannot be changed

Heredity is BEST described as natural abilities that cannot be changed. Heredity is the transmission of traits (physical and genetic qualities) such as eye color, skin color, from parents to their offspring through asexual reproduction or sexual reproduction. The inherited traits are transmitted from one generation to the next through DNA (deoxyribonucleic acid); a genetic molecule that encodes genetic information.  

Heredity is BEST described as B. natural abilities that cannot be changed.

Explanation:

Heredity or inheritance is the transmission of specific traits from the parents to their offsprings. These traits can include eye color, type of hair, hair color, skin color, abilities such as the rolling of the tongue, etc. The way that they are transmitted is by DNA molecules that will pass the traits from one generation to the next one.

this is true my friend.