Answer: D
Explanation: The consumption of fish especially the small fish e.g shellfish is by far the most significant source of ingestion-related mercury exposure in humans and animals.
The higher biodiversity in an ecosystem means that there is a greater variety of genes and species in that ecosystem. A great variety of genes and species means that the ecosystem is better able to carry out natural processes in the face of external stress. Thus, the ecosystem is more sustainable.
Hair and nails are part<span> of the integumentary </span>system<span>.</span>
I believe the answer is head-on and port (left). The side lights are usually visible to vessels approaching from the front or the side. The red light usually indicates a vessel's port (left) side while the green light indicates a vessel's starboard (right) side. These lights ensure that there is safety at night as the vessels navigate.