Q. Let S = {1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21}. What is the
smallest integer N > 0 such
that for any set of N integers, chosen from S, there must be two distinct integers that
divide each other? IZ

• (A) 10
• (B) 7
• (C) 9
• (D) 8