Question 519General Subjects - Assistant Engineer

The correct answer is A. Figure A would be the least desirable for use as a set screw because it has a flat head, which provides the least amount of gripping surface area compared to the other options. Set screws are typically designed with a pointed or tapered end to allow them to grip the mating component more securely. Figures F, G, and L all have more desirable pointed or tapered head designs that would provide better grip and holding power compared to the flat head of figure A.