Dear Priya,
Whatever reply you give, the interpretation will depend on the mindset of the interviewer.
HR Manager's Perspective
If an HR Manager takes your interview, he/she might be pleased, as it may be perceived that, although the candidate has an opportunity to assist her husband, she is choosing to grow in the field of HR. The candidate wishes to match her career growth with her qualifications, which is a tribute to the HR fraternity as a whole. He might be happy about this decision.
Businessperson's Perspective
On the contrary, if a hard-nosed businessperson or the MD of the company takes your interview, he/she may perceive that generally, wives assist their husbands in their business. Though the candidate has a great opportunity to do so or to get exposure in other departments, she is abandoning the opportunity and wishes to grow only in one department. Running one's company requires learning on the go. The interviewer may perceive that the candidate lacks a learning attitude, hence her decision to stick to one field. Please note that a large number of businesspersons do not place HR professionals on par with their counterparts but a notch below. Amongst them is a tribe that considers HR as nothing but glorified clerks!
Mixed Perspective
The third school of thought could emerge from a mix of either of the above. The interviewer may think that the candidate could be using their company to widen her exposure in the field of HR. She could use their company for practical training and quit once she gets sufficient exposure. Therefore, they may consider that the candidate is not trustworthy.
Therefore, whatever reply you give, how it will be perceived cannot be predicted. In what direction the thought process of the interviewer could go cannot be anticipated.
These are my thoughts.
My personal opinion is not to quit your company at all. Instead, you may enlarge the scope of your work. Start handling operations or business development. Working for oneself is a pleasure. Notwithstanding the higher remuneration that other companies might offer, this pleasure can never be derived by working for someone (that is, by becoming an employee)! However, the final decision is yours.
All the best!
Dinesh Divekar