I'm following one of the examples from my textbook on the Pumping Lemma:
Let C = {w | w has an equal number of 0s and 1s}
Condition 3 stipulates: |xy| <= p
If |xy| <= p, then y must consist only of 0s, so xyyz is not in C.
Therefore s cannot be pumped
I'm having trouble understanding how condition 3 leads to the conclusion that "y must only consist of 0s, so xyyz is not in C"