Question

Which symbol on a regulatory marker is used to warn of a rock or other underwater hazard?

Answer 1

Answer: Diamond shaped regulatory marker.

Explanation: The regulatory markers are those symbols that are used in order to guide us about any particular place. It warns about the area, how the situation could be, how dangerous it could be, and what are the things that we are not suppose to do. So these informations must be carefully noticed and obeyed.

In order to warn about a rock or any other underwater health hazardous situation, a diamond-shaped marker is generally used in which the diamond shape is made of orange color and the writings are done in black ink.

Answer 2

Had to look for the options and here is my answer.
The symbol that is being described above referring to a regulatory marker which is used as a warning of a rock or any hazard underwater is an ORANGE DIAMOND. Hope this answers your question.