Please answer the following question: Fact 1: Treating water is used to remove harmful substances before drinking. Fact 2: Arsenic, a naturally occurring substance, contaminates water sources in many countries. Given the two facts above, answer the question "What is treating water used to remove before drinking?" with the following options: - arsenic - air - cellulose - chemicals - Collagen - loose dirt - water vapor - ice
Answer:
arsenic