How can we ( ) the barriers of fear and hostility which divide

How can we ( ) the barriers of fear and hostility which divide the two communities?
A、break down
B、break in
C、break out
D、break up
【正确答案】：A
【题目解析】：break down 打破抛锚，break out 爆发，break up打碎，破碎，句子含义为我们如何打破分裂两个国家的恐惧和敌对壁垒？