I was first short-listed on the basis of my resume. Then, I was asked a few questions about PR, and how I would handle certain situations. I was given three different topics to chose from, they mainly revolved around the Education and Healthcare sector, as these are the sectors they generally take care of. And was asked to write an essay on any one of these topics. (They do this so they know you're on the same wavelength as the person hiring you)
Few more questions on PR and personal life, and that's about it.