I would say sight because all these details are helping me picture the setting and characters
<span>Exotics and indigenous weeds include some of the most <em><u>LETHAL</u></em><em><u /></em><u /> species: their visual impact often eclipses that of nearby plants.
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Answer:
Try researching more on the topic of your paper, and cite sources because a lot of teachers check for plagarism so citing would get you out of that category. Furthermore, if you do decide that you cited to much rephrase the words to make it sound different yet about the same topic.
Those are some helpful tips, hope they helped