第26639题 单选
下列Python二分查找函数的横线处应填写的代码是?
def search(arr, x):
    low = 0
    high = len(arr) - 1
    while low <= high:
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        if arr[mid] == x:
            return mid
        elif arr[mid] > x:
            high = mid - 1
        else:
            low = mid + 1
    return -1
A

mid = (low - high) // 2

B

mid = (low + high) // 2

C

mid = (low + high) / 2

D

mid = (low - high) / 2