单选题 Foreign military aid was prolonging the war.
A. broadening B. worsening C. extending D. accelerating

【正确答案】 C

【答案解析】动词prolong的意思是“延长、使……更长”。extend有这个意思，如：The term of office will be extended from three years to four.(任期将从三年延长为四年)。broaden是“使变宽”的意思，worsen变得更坏，accelerate加速。