A procurement officer who receives a timely protest shall comply with this section. On receipt of a timely protest, a procurement officer: shall review the substance of the protest; may request additional information or substantiation through an appropriate procedure; may discuss with interested parties and, if appropriate, may conduct negotiations with the person initiating the protest; and shall comply with any applicable regulations. Unless clearly inappropriate, the procurement officer shall seek the advice of the Office of the Attorney General on any legal issues raised in the protest. Subject to subsection (b) of this section and consistent with the State budget and other applicable laws, the procurement officer shall: resolve the protest; wholly or partly deny the protest; or wholly or partly grant the relief sought by the person who submitted the protest. The procurement officer promptly shall send the decision in writing to the reviewing authority. Unless otherwise provided by regulation, the decision of the procurement officer shall be reviewed promptly by: the head of the unit or the head’s designee; and the head of the principal department or other equivalent unit of which the unit is a part or the head’s designee. The action of the reviewing authority under this subsection shall be the final action of the unit. A decision to deny a protest is a final action for the purpose of appeal to the Appeals Board. The failure to issue a decision or issue a written notice of the anticipated decision date on the protest within 90 days after receipt may be deemed, at the sole option of the protestor, to be a decision to deny the protest.