Which two types of customers dislike day-to-day changes in hardness, taste, temperature, or chemical composition?

• A. Residential and commercial
• B. Industrial and domestic
• C. Agricultural and industrial
• D. Public and private

Answer: (B)

The main idea is that some customers need water quality to stay the same from day to day. Industrial users rely on consistent hardness, taste, temperature, and chemical composition to maintain product quality, protect equipment, and keep processes running smoothly—any daily swing can cause defects, scaling, or corrosion. Domestic (residential) customers also expect stable water for drinking, cooking, and daily use; noticeable changes in taste or other properties are undesirable in homes. Other pairings don’t capture this shared need for daily stability in water quality as strongly, since they group customers in ways that don’t directly reflect sensitivity to everyday fluctuations. So, industrial and domestic are the two types most averse to day-to-day changes in water quality.