Scientific investigations often lead to the formulation of new scientific questions. the observations charles darwin made during his time aboard the h. m.s. beagle prompted him to ask which question

That whether the gathering of slow changes in a population results in the formation of a new species over time?

Explanation:

The man behind the concept of natural selection is Charles Darwin, that certain kinds of traits, which provide relative benefit would generally appear more and more, and finally modifying the species with time. Thus, the gathering of slow changes in a population results in the formation of new species with time. The discovery made by Darwin was associated with selective breeding, however, his prime agenda was gradual selection, not the breeding itself.

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)]

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds