Which statement(s) below is/are correct?

Valleys are more susceptible to radiation fog than hill tops
Without the summer fog along the coast of California, redwoods would not grow well there
Fog can be composed of ice crystals
All of the above are correct

The correct answer is: D. All of the above are correct.

  • Valleys are more susceptible to radiation fog than hill tops because cold air sinks and collects in valleys. This cold air can hold less moisture than warm air, so it can’t hold as much water vapor. When the air cools enough, the water vapor condenses into fog.
  • Without the summer fog along the coast of California, redwoods would not grow well there because the fog provides moisture that the redwoods need to survive. The fog also helps to cool the air, which is important for redwoods because they are sensitive to heat.
  • Fog can be composed of ice crystals when the air is very cold. When the water vapor in the air condenses onto tiny particles of dust or salt, it forms ice crystals. These ice crystals can be very small, and they can be so light that they float in the air.

In conclusion, all of the statements above are correct.