Diane is the project manager of the HGF Project.

The risk owner is the individual on the project team that is closest to the risk event. The risk owner can be an individual or an organization responsible for implementing risk responses or contingency plan. The risk owner should be empowered with the ability to respond to the risk as it was planned.

Answer option A is incorrect. Diane is the project manager and likely won't be the risk owner as well.

Answer option B is incorrect. The project sponsor authorizes the project but does not participate in the execution of the project.

Answer option D is incorrect. While a subject matter expert may be the risk owner on some occasions, he won't be the risk owner on every occasion.