Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: How do the waxy stem covering and needle-shaped leaves improve the ability of a cactus to survive in the desert?
They reduce the loss of water from the plant to the air.
The waxy stem covering reduces water loss and the needle-shaped leaves minimize water evaporation.