Database: video_games
Question: List the platform ID of the game titled Airborne Troops: Countdown to D-Day.
SQL: SELECT T1.platform_id FROM game_platform AS T1 INNER JOIN game_publisher AS T2 ON T1.game_publisher_id = T2.id INNER JOIN game AS T3 ON T2.game_id = T3.id WHERE T3.game_name = 'Airborne Troops: Countdown to D-Day'