Answer:
Step-by-step explanation:
We are to rank the options given in the question to correctly prove the theorem that: "If A & B are set, and A is a subset of B"
To arrange the steps in the correct order, we have:
(a) Assume that B is countable
(b) The elements of B can be listed as b1, b2, b3
(c) Since A is a subset of B, taking the subsequence of {bn} that contains the terms that are in A gives a listing of the elements of A.
(d) Therefore A is countable, contradicting the hypothesis.
(e) Thus B is not countable