The bolded word here is the BESTSELLER. This kind of complement is a direct object complement. The adjective overnight denotes to the object bestseller which is an adjective. Another adjective complements another adjective, thus, the term direct object.
I’m presuming the last one is supposed to be bias, but that’s the one that has a negative connotation to it.
The answer is D. It helps you revise your research focus as you uncover more information
I believe the answer is A, because Gandalf was angry that Butterbur was delaying in bringing him news
