Loop Invariant for Array Comparison

Consider the following countCommon method, which is intended to count the number of common elements between two sorted integer arrays.

/** Counts the number of common elements between arrays v and w.
* Precondition:
* - v is an array of int sorted in increasing order
* - w is an array of int sorted in increasing order
* - N is the number of elements in array v
* - M is the number of elements in array w
* - v[0] < v[1] < ... < v[N-1] and w[0] < w[1] < ... < w[M-1]. */

public static int countCommon(int[] v, int[] w, int N, int M) {
    int vIndex = 0, wIndex = 0, count = 0;
    while (vIndex < N && wIndex < M) {
        if (v[vIndex] == w[wIndex]) {
            count++;
            vIndex++;
            wIndex++;
        } else if (v[vIndex] < w[wIndex]) {
            vIndex++;
        } else {
            wIndex++;
        }
    }
    return count;
}

Which of the following assertions is true after each complete iteration of the while loop?