In primary production oxygen utilized by animals is less than the oxygen consumed by autotrophs proteins are made by animals carbon dioxide is released into the water oxygen is utilized by plants there is a net gain in organic carbon by organisms

There is a net gain in organic carbon by organisms

Explanation:

Primary production refers to the total biomass produced by producers. It mainly includes the organic matter produced by the photosynthetic activity of green plants using the energy of sunlight. Since the process of primary production includes the production of organic matter, the organic matter present in living beings is increased.

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.