The correct answer is: joined.
The charm of an Austrian gentleman, the brutality of a gangster, the ranting of a demagogue, the assurance of a diplomat all joined together to create a kaleidoscope of performance. This means that the different aspects of the performance were combined to create a unique and interesting effect.
The word “succeeded” means to come after and take the place of something else. This does not make sense in the context of the sentence, as the different aspects of the performance are not replacing each other.
The word “struck” means to hit or cause a sudden blow. This does not make sense in the context of the sentence, as the different aspects of the performance are not hitting each other.
The word “touched” means to feel or come into contact with something. This does not make sense in the context of the sentence, as the different aspects of the performance are not touching each other.
The word “joined” means to come or put together so as to form a single unit. This makes sense in the context of the sentence, as the different aspects of the performance are combined to create a single performance.