What is more important in a movie trailer sound or images?

I personally think that in a movie trailer sound and images go hand-in-hand. Because even though an image can be very powerful it doesn't build atmosphere and mood as well as if it had been coupled with music. At the same time sound effects can build drama but for advertising a film it is better to have images. This way you can build tension with silences and you can also advertise the stars in the film.