OE
“While” indicates that the clause after the comma will oppose the clause before the comma. So instead of supporters, you want opposers. The word “condemned” further hints that the first blank will be something like opposers/condemners. Only “detractors” works. “Interlocutors” (go-betweens) and “contemporaries” (people who lived at the same time) do not fit the desired meaning. For the second blank, you want a description that a detractor would apply to “earthy speech.” So you want earthy, but in a bad way —perhaps coarse or unrefined would serve. The word fits those descriptions. “Obtuse” (unintelligent or ignorant) is negative but does not match the clue “earthy.” In contrast, “genteel” (polite) is almost the opposite of what you want.
Answer: B,D