- Lower is similar to decreasing
- Temperature is a measure of heat energy
- Colder means lower in temperature
- Therefore, colder means a decrease in heat energy

- Colder means a decrease in heat energy
- Air is rising to a colder region
- Hence, the heat energy of the air will decrease when air is rising to a colder region

- Atmosphere means air
- Water vapor is found in the atmosphere
- Therefore, air contains water vapor

- The heat energy of the air will decrease when air is rising to a colder region
- Air contains water vapor
- Therefore, the water vapor in air will decrease in heat energy when air is rising to a colder region

- Condensing means a substance changes from a gas into a liquid by decreasing heat energy
- Water is a kind of substance
- Hence, water condensing is when water changing from a gas into a liquid by decreasing heat energy

- Water condensing is when water changing from a gas into a liquid by decreasing heat energy
- Water is in the gas state , called water vapor
- Water is in the liquid state, called liquid water
- So, water condensing is when water changing from water vapor into liquid water by decreasing heat energy

- The water vapor in air will decrease in heat energy when air is rising to a colder region
- Water condensing is when water changing from water vapor into liquid water by decreasing heat energy
- Therefore, air rising into a colder region will cause the water vapor in air to condense

- Air rising into a colder region will cause the water vapor in air to condense
- Clouds are formed by water vapor rising into colder regions of the atmosphere and condensing into rain droplets
- Therefore, air rising into a colder region will cause the water vapor to condense into rain droplets

Hence, air rising into a colder region will cause the water vapor to condense into rain droplets
Question: Which of these could cause water vapor to condense into rain droplets?
Context: - Condensing means a substance changes from a gas into a liquid by decreasing heat energy 
- Water is a kind of substance 
- Water is in the gas state , called water vapor 
- Air is rising to a colder region 
- Temperature is a measure of heat energy 
- Colder means lower in temperature 
- Clouds are formed by water vapor rising into colder regions of the atmosphere and condensing into rain droplets 
- Water is in the liquid state, called liquid water 
- Water vapor is found in the atmosphere 
- Lower is similar to decreasing 
- Atmosphere means air