That would be A, an adjective phrase. :)
The best option is D studied.
This word denotes a measured, even-handed approach to the issue. So, it should be :Current immigration policy must be studied before new proposals can be made.
In "The Devil and Tom Walker," Washington Irving criticizes the selfish and heartless sections of American society, especially usurers, by satirizing them through Tom Walker’s character. He also criticizes the hypocrisy of American religious groups through his satirical description of Tom’s churchgoing and through his mention of the Salem witch trials and the persecution of Quakers and Anabaptists. He also seems to suggest that American society was founded on violence and inequality:
"Since the red men have been exterminated by you white savages, I amuse myself by presiding at the persecutions of Quakers and Anabaptists; I am the great patron and prompter of slave dealers, and the grandmaster of the Salem witches."
From Plato
There are 3 syllables in <span>contentious </span>
I think this is definitely WHO because the story is talking about a certain unknown character.