A. There's no satisfactory answer to this one. Theoretically,even though the Italian "ballerina" means simply "female dancer,"only a *principal* female dancer is supposed to be called aballerina. If that restriction were universally observed, thenthe nearest male equivalent would be the French premi`er danseur("first dancer"). But in practice, people use ballerina to referto any female ballet dancer, and in that case all you can say is"dancer" for the male.
I suppose you could be pedantic and use the Italian masculineform ballerino, but people probably wouldn't understand you and,worse, are likely to mis-hear the word as "ballerina," whichcould lead to endless confusion.
Tom