Final answer:
Grab bars should be installed on the side wall closest to the water closet and on the rear wall, following the ADA guidelines to ensure restroom accessibility for individuals with disabilities.
Step-by-step explanation:
The question is regarding the placement of grab bars in relation to a water closet, which is a component of restroom accessibility standards. According to the Americans with Disabilities Act (ADA) guidelines, grab bars should be installed on the side wall closest to the toilet and on the rear wall to provide adequate support for individuals with disabilities. These grab bars help facilitate safe and independent use of the restroom facilities. The side wall grab bar should be mounted no more than 12 inches from the back wall and should extend at least 54 inches from the back wall. The rear wall grab bar should be at least 36 inches long and mounted at a height between 33 and 36 inches from the floor.