What about it? What’s the question
B. Leaf cells. Because the rest aren’t right I think
In geology, a key bed (syn marker bed) is a relatively thin layer of sedimentary
rock that is readily recognized on the basis of either its distinct
physical characteristics or fossil content and can be mapped over a very
large geographic area.[1]
As a result, a key bed is useful for correlating sequences of
sedimentary rocks over a large area. Typically, key beds were created as
the result of either instantaneous events or (geologically speaking)
very short episodes of the widespread deposition of a specific types of sediment. As the result, key beds often can be used for both mapping and correlating sedimentary rocks and dating them. Volcanic ash beds ( and bentonite beds) and impact spherule beds, and specific megaturbidites
are types of key beds created by instantaneous events. The widespread
accumulation of distinctive sediments over a geologically short period
of time have created key beds in the form of peat beds, coal beds, shell beds, marine bands, black in cyclothems, and oil shales. A well-known example of a key bed is the global layer of iridium-rich impact ejecta that marks the Cretaceous–Paleogene boundary (K–T boundary). Please let me know if it works.
<h2>Answer:</h2>
The pH of the pond water and survival rate of animal species living in the pond has a direct relationship with each other. Animal species can survive at a specific level of pH"Optimum pH" at which these species can show their maximum activity.
If we decrease the pH the pond water will become more acidic and it will become challenging for species to survive in the acidic environment and if we increase the pH the water becomes more alkaline and again it affects the marine life. So, the pH of pond water should be in normal ranges.
