ANSWER: C, the continents were at one time joined together.
REASONING: Alfred Wegener was the first person to propose the scientific theory of Continental Drift. Continental Drift is a theory that supposes all the continents were at one time joined together as one large land mass. The mechanisms of continental drift can be explained by Plate Tectonics.
Answer:
Upwelling bring up nutrients (deep sea water is rich in nutrients), this supports the growth of plankton and seaweed. This then provides food for fish, marine mammals, and birds.
Uracil is not found in DNA, only RNA, and replaces thymine in RNA
