单选题 In times of war, we must take precautions against acts of ______ as well as of direct violence.
【正确答案】 B
【答案解析】(sabotage阴谋破坏，破坏活动)。句意为：在战争时期，我们既要防止直接的暴力又要防止暗中破坏。A．viciousness恶毒；C．pretext借口；D．hatefulness可恨。