...grandmaster flash I think
The most often used application of the term virtuosity applies to music - a virtuosic piece, a virtuosic musician etc. Thus the answer to this is b. Virtuosity means extreme technical proficiency in an area of music (though it can be applied to other things as well to show mastery of a skill - a virtuosic painter etc.)
The answer is b) musicians because they are the one that preform in public!
