I believe the answer should be encantan
Tu because If you put Mi or mis son rojos it says my are red which dosen't really make sense. Since you put tu in front of son (plual) it would be they are red.
Answer:
Dependent
Explanation:
They are parasitic for survival. Cannot just do it all alone but rely on others.
3.7 is past tense so pasado and 3.8 is present tense so presente
