Question: How do the waxy stem covering and needle-shaped leaves improve the ability of a cactus to survive in the desert?

  Options: 
 A. They make the plant appetizing to small desert animals.
 B. They prevent the loss of oxygen through photosynthesis.
 C. They reduce the loss of water from the plant to the air.
 D. They provide the storage space for different types of minerals.
Answer: C