There is a height-balanced tree T storing n elements. The greatest element smaller than x in T is called the predecessor of s in T. Given any positive number k, we wish to compute k predecessors of x in T. What is the time complexity of the best algorithm that can do this task?
A. O(k + log n)
B. O(k log n)
C. O(log(n + k))
D. O(n + k)