Do you think that you need to improve on some skills, or gain some knowledge, to be able to handle the new role?

The best possible answer to this question should be the combination of shyness and self-confidence. Because in this new role you will be responding to some new duties and experience new situations.

You have to ensure that the interviewer should believe that you do not consider yourself as the perfect person for this role. You have to make him believe that there are certain things on which you need to improve on and some new things or skills you need to learn. Correspondingly, you have to show your learning ability and enthusiasm towards learning other skills; so that you can successfully transit to the new position. Your attitude should be very positive and can handle criticism.