In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.

Example input: This list contains the top 25 accounts with the most followers on the social photo-sharing platform Instagram. As of May 2018, the most followed user is Instagram's own account, with over 235 million followers. Selena Gomez is the most followed individual, with over 137 million followers. Ten accounts have exceeded 100 million followers on the site.
Example output: who has the maximum number of followers on instagram
Example explanation: The answer is talking about the Instagram accounts that have the most followers. The question asking about the maximum number of followers. So this is a good example.
Q: Emery boards are generally less abrasive than the metal nail files, and hence, emery boards may take longer to file down nails than metal nail files. However, nail files may play a role in disease transmission if they are used on more than one person without adequate sterilization. Emery boards are usually less expensive than metal nail files, therefore emery boards can be economically disposed of after use on a single person. The nail can be smoothed and shaped accurately by taking light, even strokes in one direction across the top of the nail. Twenty to thirty easy strokes can typically shorten excessively long fingernails, while five to ten strokes are sufficient for shaping the nails.
A:
what is the difference between emery board and nail file