单项选择题
Why do we usually not use BBST to implement priority queue?
为什么我们通常不用BBST实现优先级队列？
A．Time efficiency is not high enough时间效率不够高
B．BBST is too complex for simple functions in priority queues对于实现优先级队列的简单功能来说，BBST过于复杂
C．BBST is not what we are going to learn in this chapter.我们本章要学的不是BBST
D．The vector is more efficient向量的效率更高
