Apolytypic species is: (a) one that has no phenotypic variability has never been observed in nature (b) is one composed of local populations that differ from one another with regard to the expression of no more than three traits
(c) is one that has no phenotypic variability.
(d) is composed of widely dispersed populations.
(e) has never been observed in nature.

(D) is composed of widely dispersed populations.

Explanation:

A polytypic species is the one that is composed of various local populations. These local populations differ from each other with respect to one or more genetic traits. Each of the local populations that make a polytypic species exhibit genetic variations among its individuals.

For example, individuals from the local population of human exhibit variations for genetic traits such as skin color, hair color, etc.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus. this is so because calcium carbonate is the main component in the shells.

explanation:

well we can't tell you because we cant see the time give a screen shot or something.