The lack of sunlight in the deep ocean limits the types of organisms that can survive. ;
the lack of sunlight in the deep ocean limits the types of organisms that can survive
The decrease in the diversity of organisms from shallow seas to deep oceans is primarily due to the lack of sunlight in the deep ocean, which limits the types of organisms that can survive. The photic zone supports diverse life through photosynthesis, while the aphotic zone accommodates only those organisms adapted to low or no light. Therefore, the best answer is option D.
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