if you read the question. you will notice that they have asked for number of states in minimal FA that can accept the given sequence of strings.
and #states minimum FA = minimum(DFA,NFA)
=NFA
as nfa will always have #states <= Dfa #states.
as for the given question we will have 5states for NFA and 6states for DFA.
so the answer should be 5states for minimal finite automata.
and 6 if they have asked for minimal DFA.