Each of us has some interests. While someone loves webdesign, someone else is into designing clothes, or buildings. Some guys may love to be involved in product management, having a role of designers and taking care of all the project in its complexity.
However, you should forget on your own interests for a while, and think about the interests of an employer. You should say that you like what they design.
To be able to do it you need to do your homework. Spend some time on their website, check the portfolio, find out what kind of design they are into and stick to it in your answer. Job description should also help you.
It would be tiring and dreadful to work on projects you aren’t into yourself. I know that we need some job to make money… But you should chose a job that will make you happy in your daily life.
I really like webdesign, especially designing sites for mobile devices. I would like to specialize on this field with huge potential. That is also the reason why I decided to apply for the job in your company, as I see you’re quite heavily into this field.
I love creative design. The portfolio of your company amazed me on the very first glance, as I saw a lot of creativeness in each piece of work. Therefore I can see myself fitting pretty well in your company. I have on my mind already some ideas for your existing campaigns.