What part of the nail is known for providing protection to the fingertip?

The free edge of the nail is the portion that extends beyond the fingertip, providing a barrier and protecting the sensitive tissues beneath it. This outermost part plays a crucial role in preventing injuries to the fingertip and contributing to the overall structure and appearance of the nail.

While the other options are significant parts of the nail structure, they serve different roles. The nail matrix is involved in nail growth and does not provide direct protective function to the fingertip. The hyponychium, located just under the edge of the nail, helps secure it to the fingertip but is not the visible part that protects. The lunula, which is the white crescent shape at the base of the nail, is also not involved directly in fingertip protection but is part of the matrix where new nail cells are produced.

Overall, the free edge is essential for safeguarding the fingertip against external elements, making it the correct choice for this question.