Question

he voiced the slogan at a news conference, on twitter and even at his weekly cabinet meeting sunday.
in this sentence, voiced means:
disapproved of openly
uttered sounds or words
argued in support of
expanded or added detail to

Explanation:

In the context, "voiced" means expressing or stating an opinion. Among the options, "argued in support of" best fits as he is expressing his stance (the slogan) in various public - like settings. It's not about disapproving, just stating; "uttered sounds or words" is too literal; and "expanded or added detail to" is not what's implied.

Answer:

C. argued in support of