There are no tricks to this one. Tell the interviewer briefly and straightforwardly about your CPA or other certifications or your progress toward them:
“I don’t have my CPA license yet but I am actively working toward it. I have passed two out of four parts—BEC and FAR—and am planning to take the other two sections within the next six months.”
On the other hand, if you have a CPA, you might answer like this:
“I obtained my CPA during the first two years of my career and have maintained it ever since—keeping up with the CPE annual requirement by attending trainings and conferences. I am also pursuing my CFE as I’ve developed an interest in forensic accounting and that certification will be valuable for the direction my career is going in.”