A(n) is formed when groundwater that flows in an aquifer between two layers ofimpermeable rock is forced to the surface by an increase in pressure,oa artesian wellob. aquiferoc. springod. man-made well

A. artesian well

Explanation:

The artesian well represents a well that is pumping out water on the surface in a natural way, thus not needing any human assistance. The water is coming vertically or diagonally upward toward the surface from an aquifer that lies below it. This happens when there's an aquifer between two impermeable layers of rocks, so when there's new water flowing in it, it can not accumulate it, so the pressure rises and the water is pushed up on the surface where there are the cracks or softer rocks. The artesian wells are relatively common, and they usually are not large, but pump out smaller amounts of water, creating small streams.

If your question is:  Which two structures would the scientist most likely see? Then:

A scientist is using a microscope to observe a type of bacteria. The scientist most likely see cell wall and vacuole.