Yet in several regions of Africa, there is serious shortage of freshwater. Researchers have been developing methods to collect moisture from fog for daily water use as if it were rainwater. The difference is that fog is simply more common than rain. Fog forms when the land releases heat at night. As the ground cools down, it causes water molecules in the air to condense.Fog collection works by utilizing mesh (网状物)hung in the air. The mesh is spread between two poles facing the general direction of the wind. The wind naturally pushes the fog toward the mesh, where water accumulates. As the water drops get bigger, they flow down to a pipe into a tank. This method can produce around 20 gallons (加仑)of water per mesh, which is enough for a family's daily needs. The entire system is also low-maintenance without the need for electricity.The steady supply of water has allowed communities to develop in many other ways. Locals no longer fall victim to water anxiety or the constant worry of finding water. Women can spend more time taking care of their children instead of walking long distances to collect water. The improved facilities have also opened opportunities for men to work consistent jobs.While this solution has helped many communities globally, it presents future questions. For one, such systems work best in rural regions. They don't work in cities for lack of space. Secondly, atmospheric water only makes up 0.004% of the freshwater found on the planet. Therefore, this system can only help small communities. Furthermore, climate change also affects the amount of fog in a region's climate, so there may also be a limit to how long this system can work. Which of the following is the best title for the passage?

Passage 2Questions 36 to 40 are based on the following passageFor most of us, having drinking water is a privilege we often take for granted. Yet in several regions of Africa, there is serious shortage of freshwater. Researchers have been developing methods to collect moisture from fog for daily water use as if it were rainwater. The difference is that fog is simply more common than rain. Fog forms when the land releases heat at night. As the ground cools down, it causes water molecules in the air to condense.Fog collection works by utilizing mesh (网状物)hung in the air. The mesh is spread between two poles facing the general direction of the wind. The wind naturally pushes the fog toward the mesh, where water accumulates. As the water drops get bigger, they flow down to a pipe into a tank. This method can produce around 20 gallons (加仑)of water per mesh, which is enough for a family's daily needs. The entire system is also low-maintenance without the need for electricity.The steady supply of water has allowed communities to develop in many other ways. Locals no longer fall victim to water anxiety or the constant worry of finding water. Women can spend more time taking care of their children instead of walking long distances to collect water. The improved facilities have also opened opportunities for men to work consistent jobs.While this solution has helped many communities globally, it presents future questions. For one, such systems work best in rural regions. They don't work in cities for lack of space. Secondly, atmospheric water only makes up 0.004% of the freshwater found on the planet. Therefore, this system can only help small communities. Furthermore, climate change also affects the amount of fog in a region's climate, so there may also be a limit to how long this system can work. Which of the following is the best title for the passage?

• A. More Victims to Water Shortage
• B. The Importance of Freshwater
• C. Harvesting Water from Air
• D. An Easy Way to Collect Rainwater