Which biogeochemical cycle includes the exoskeleton and shells of marine organisms as a reservoir? carbon nitrogen sulfur oxygen

The correct option is OXYGEN.
The biogeochemical cycle refers to the pathway by which a chemical element is moved through both the abiotic and biotic compartment of an ecosystem. Each element has its own cycle through which it is recycled.
Marine organisms in the biosphere usually create carbonated shells which are rich in oxygen, when these organisms die they serve as a source of molecular oxygen.

Swaves do not travel through water and stuff like that p waves do

It is the doctrine that the us had the right and duty to expand throughout north america. it just means they believed they had the right to expand westward and they did! they stated with the 13 colonies and then they kept moving gaining different territories throughout the years