In a transformer, there is a primary voltage of 70V and a secondary voltage of 210V. Which statement best describes this transformer?

It’s a step-up transformer because the secondary voltage is greater than the primary voltage.
It’s a step-up transformer because the primary voltage is greater than the secondary voltage.
It’s a step-down transformer because the secondary voltage is greater than the primary voltage.
It’s a step-down transformer because the primary voltage is greater than the secondary voltage.