Answer:
[tex]\large\boxed{A\subseteq B}[/tex]
Step-by-step explanation:
[tex]A=\{1,\ 2,\ 3\},\ B=\{3,\ 2,\ 1\}\\\\4\in A-FALSE,\ \text{because only}\ 1\in A,\ 2\in A\ \text{and}\ 3\in A\\\\A\subseteq B-TRUE,\ \text{because any elements of A are the elements of B.}\\\\A\ \text{is infinite set}-FALSE,\ \text{because set A has a finite number of elements}\\\text{(three elements)}\\\\\O\notin B-FALSE,\ \text{because the empty set is subset of any set.}[/tex]
