Which of the following is a core activity of plumbing?

The core activity of plumbing primarily involves the distribution of the water supply and the drainage of waste. This encompasses the installation, maintenance, and repair of piping systems that carry potable water into buildings as well as the removal of wastewater. Plumbing systems are essential for the proper sanitation and functionality of any residential or commercial structure, impacting health and safety by ensuring that clean water is available and waste is effectively disposed of.

In contrast, the other options pertain to activities that, while they may take place in conjunction with plumbing, fall outside its defined scope. Installing electrical systems relates to electrical work, constructing structural frameworks pertains to carpentry and structural engineering, and providing heating solutions involves HVAC (heating, ventilation, and air conditioning) work. Each of these fields has its own set of practices and regulations, distinct from those governing plumbing. Thus, properly understanding the primary activities of plumbing is essential for anyone in the field to ensure compliance with relevant codes and practices.