Which type of water is considered satisfactory for drinking and free from pollution and contaminants?

Potable water is defined as water that is safe for human consumption and free from harmful contaminants and pollutants. This type of water meets health standards set by regulatory bodies and is treated to remove impurities that could pose health risks. The treatment processes involved in ensuring water is potable include filtration, disinfection, and various chemical treatments, which help eliminate pathogens, toxins, and any other potentially harmful substances.

In contrast, gray water is wastewater generated from household activities such as washing dishes, laundry, and bathing. It may contain substances that, while generally less harmful than sewage, are still not safe for drinking. Rainwater, while collected fresh and potentially clean, can pick up pollutants as it flows over surfaces before being stored, making it unsuitable without proper treatment. Reclaimed water is treated wastewater that is reused for non-potable purposes, such as irrigation or industrial processes, but it is also not safe for drinking unless it undergoes advanced treatment to meet potable standards.

Thus, among the options listed, potable water is the only type that is specifically defined as safe for drinking and free from contaminants, making it the correct answer to the question.