OEHis handling of the scandal was successful, so adroit (skilled, adept) fits best. Neither penitent (sorry for sin) nor heterogeneous (mixed; composed of differing parts) “handling of the ... scandal” is supported by proof in the sentence. The scandal seemed poised to ruin things—that is, it hadn’t done so already. What makes the most sense here is that the scandal itself hadn’t quite broken yet—it was only looming (taking shape as an impending event). Someone might be fretful (worried) over a scandal, but fretful doesn’t make sense as a description of the scandal itself. There are no indications in the sentence that the scandal was ecumenical (worldwide in scope).
Answer: B,E