How many of Gary Trousdale's movies are adventure movies?
Gary Trousdale refers director = 'Gary Trousdale'; the adventure movie refers to genre = 'Adventure';
SELECT COUNT(T.name) FROM ( SELECT T1.name FROM director AS T1 INNER JOIN movies_total_gross AS T2 ON T1.name = T2.movie_title WHERE T1.director = 'Gary Trousdale' AND T2.genre = 'Adventure' GROUP BY T1.name ) T