Tell the interviewer why this particular Benefits offering is exciting to you (you enjoy the tasks involved, want to help others navigate a tricky aspect of healthcare, or find the complexities of the law fascinating, etc.). If you had the opportunity to review the company's benefit offerings prior to the interview, mention detail of their specific benefit to show you have done your research.

"There are so many aspects of Benefits that I enjoy, from helping people navigate the complexities of our healthcare system to running the reporting to stay compliant with ACA laws, but I honestly find Flexible Spending Accounts (FSAs) to be fascinating. They aren't new or even flashy, but they have so much to offer. FSAs often fly under the radar and employees either don't realize their employer offers an FSA or don't understand what an FSA can do for them. I really like talking to employees about the ways an FSA can save them money and how they can best plan to utilize it, and I even developed a spreadsheet to help employees decide how much to put in it for the year. I saw in the benefit guide you sent me that your company offers an employer match to the FSA and I think that is such a great way to give your employees a head start in healthcare expenses each year."