Answer this question by telling the interviewer what seems great about the company, e.g., their services, initiatives, growth opportunities, and so on.
Make sure to answer by providing evidence that you did your due diligence before the interview (e.g., by mentioning something exciting you saw on the job posting, company website or social media pages), which demonstrates you are serious about working for this employer specifically and are not simply looking for any job. Link this evidence to your professional goals proving this position was made for you and it is one in which you will excel.
For instance, you can point to their seemingly friendly company culture as per some specific programs or initiatives you came across on their website, and say how friendly and how much of a team-player you are - and that this is exactly the type of work environment you are looking for.
"I saw on your website that your company is participating in the Run for the Cure benefiting the Breast Cancer Foundation. This is a great initiative contributing to the company morale by strengthening relationships while giving back to the community. I always seek the opportunity to demonstrate my team playing skills and hope to work with colleagues I will consider part of my family."