The main function of a cooling tower is to...

The primary function of a cooling tower is to remove excess heat from water, making option B the correct choice. Cooling towers are designed to dissipate heat from water that has been heated during industrial processes or through HVAC systems, allowing the cooled water to be recirculated back into the system. This process is essential for maintaining the efficiency of cooling systems and preventing overheating, which can lead to equipment failure or reduced operational efficiency.

In contrast, the other options describe functions that are not relevant to the operation of a cooling tower. Heating water for domestic use pertains to hot water systems or boilers, not cooling towers. Storing water for emergency use relates to water reservoirs or tanks and does not align with the cooling tower's purpose. Purifying wastewater typically involves treatment facilities designed to clean water, whereas cooling towers focus on heat exchange rather than water purification. Understanding these distinctions helps clarify the specific role of cooling towers in various applications.