Critical Reasoning

The water temperature in an estuary is influenced by fluctuations in air temperature to a much greater extent than is the case in the ocean. If the estuary is shallow, and the fresh and saline components are well mixed, temperature and salinity are usually the same from top to bottom, although temperatures in the shallow waters over mud flats may rise considerably in the summer. Oxygen and carbon dioxide levels in the water vary with photosynthesis, respiration, and decomposition of organic materials. Most animals can tolerate only a limited range of all the various conditions that exist in an estuary; thus each species selects that portion of an estuary where the normal changes in temperature, salinity, and the like fall within its range.

The most logical conclusion to draw from this paragraph is that
a. oxygen and carbon dioxide levels in an estuary change significantly depending on the latitude of the wetlands
b. the life forms found in the ocean are probably greater in number as compared to those found in an estuary
c. water temperature in an estuary compared to a stagnate water mass-a pond, for example- would have a profound impact on the ecological surroundings
d. photosynthesis, respiration, and decomposition of organic materials are common to all waterrelated habitats
e. evidence demonstrates that species of animals found in an estuary probably evolved from the ocean

How to draw conclusion here?