which is the time complexity of the binary-serach,该如何解决

which is the time complexity of the binary-serach
which is the time complexity of the binary-serach(using the Big-0 notation alorithm)()
 A 0(N);
 B 0(log(N));
 C 0(N/2);
 d 0(sqrt(N));
  这个题目是问二叉搜索树的时间复杂度吗? 
  using the Big-0 notation alorithm这个补充是啥意思

------解决方案--------------------
用大O表示法来表示2分查找的时间复杂度
------解决方案--------------------
B O(log(N))