If someone believes that option (A) is also correct, then following is the counter example:
Suppose
listA={10, 20, 30, 40, 50}
i=0;
j=4;
x = 60;
k = (0+4)/2 = 2
listA[2] <= 60; hence i=k+1 = 3
k = (3+4)/2 = 3
listA[3]<= 60; Hence i = k+1 = 4;
k = (4+4)/2 = 4
listA[4] <= 60, hence i=k+1 = 5
Now, i>j, so loop terminates and returns -1.