The user has provided a task that requires choosing a false sentence and then selecting a favorite flavor. However, without any context or story to accompany these questions, it's impossible to determine which sentence is false or what Sergey's favorite flavor is. Therefore, I cannot provide a definitive answer.
To answer question D, I would need to know the actual events of the tournament to identify a false statement.
To answer question E, I would need to know Sergey's preference for ice cream flavors.