Obviously the genuine reviews. With the constructive negative reviews of your business, your perception of your company improves.
To respond to a bad review:
Be courteous, articulate and professional and avoid mentioning the name of the reviewer. Check for typos. You may formulate the response in a word document then copy it . Thank the reviewer. Don't be shy from accountability and address the issue behind the complaint. Try to use the review to fix the problem.
Who should respond? Anyone who is able to speak on behalf of the company, such as managing director, public relation, marketing or human resources.