Answer:
E
Step-by-step explanation:
True long distance migrants, arctic terns nest in coastal wetlands of northern Europe.
from the options, Option E follows the proper usage of modifier and follows parallelism thus it is correct.
In option A, the use of Arctic terns and they is not necessary. the usage is awkward.
Option C is also wordy and awkward, Starting the sentence with "being" makes it awkward.