Merging States

We say that two states p and q of a DFA can be merged if $\backslash$delta $($p$,$ a$)=\backslash$delta $($q$,$ a$)$ for every letter a in the alphabet, and p and q are either both final or both non$-$final. Then if M is any DFA, and there do not exist two distinct states in M that can be merged according to this definition, then M is a minimal DFA true or false