is the process by which genes for traits that aid survival and reproduction are selected over time to allow the species to thrive.

Natural selection

Explanation:

Natural selection can be defined a process of differential survival and reproduction of members of the species as some members of the species have genes which when express are responsible for traits that can aid in the survival of the organism in its environment and also promotes its reproduction. The beneficial traits are passed from one generation to another this is responsible for sustenance of the species. It gives the survival advantage to the members of the species.

a

explanation:

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]