Which statement provides the best introduction to the passage? Marine Biology: A World Within Our World

This field studies unique underwater ecosystems and their growing influence on human beings. The variety of animal life found on land extends to the seas and oceans as well. Millions of years ago, life on earth began in giant bodies of water. Since then, marine creatures have been changing to adapt to their environment.
Predators like sharks, dolphins, and turtles have developed exceptional hunting skills, while their prey, mainly small fish, have mastered the skill of disguise to escape the predators. Squids, a shark’s favorite meal, change color to match the environment and, thus, escape their predators.
Many of these marine creatures are widely used in the study of medicine. Cod liver oil, for example, is used as an omega-3 fatty acid supplement. Marine biology aims not just to utilize, but also to conserve, this precious ecosystem.
answer choices:
marine biology is a field of science that deals with the creatures of the ocean.
the field of marine biology deals with see creatures used for medicinal purposes
the field od marine biology tries to explain the difference between land and water ecosystems
marine biology is the study of predators and prey within oceans and seas
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