Scientists determine evolutionary relationships between animal phyla using evidence from the a. fossil record. c. animal size. b. number of offspring. d. animal behavior.

The correct answer is - a. fossil record.

Explanation:

Fossil records are the records or list of fossils that are analyzed and placed in order taxonomically. Fossils are very helpful in establishing the evolutionary relationship of the animal phyla by various ays such as the age of a fossil by dating, DNA, or genetic material helps them to determine the evolutionary relationships of various species or organisms. It helps in representing the changes that took place in organisms over the period of time.

Thus, the correct answer is - a. fossil record.

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