Whenever a two-level implementation is required to be done and nothing is mentioned about using or not using complement and then assume complement of a variable are also given in advance.
Two-level implementation is basically drawn to show the minterms or maxterms involved in function.
Number of minterms = Number of AND gates needed + 1 OR gate. Number of maxterms = Number of OR gate + 1 AND gate
A Θ B = A'B OR AB' Two AND gates + 1 OR gate
A Θ B = (A' + B') AND (A + B) Two OR gates + 1 AND gate