Fill in each numbered blank with one suitable word or phrase.

Desert biomes are the (1) _____ of all the biomes. In fact, the most important characteristic of a desert is that it receives very little (2) _____. Most deserts receive less than 300 mm a year compared (3) __ rainforests, which receive over 2,000 mm. That means that the desert only gets 10 percent of the rain that a rainforest gets! The temperature in the desert can (4) _____ drastically from day to night because the air is. (5) _____ dry that heat escapes rapidly at night. The daytime temperature averages 38°C (6) _____ in some deserts it can get down to -4°C at night. The temperature also varies greatly depending on the (7) _____ of the desert.

Since desert conditions are so severe, the plants that live there need to have (8) _____ to compensate for the lack of water. Some plants, such as cacti, (9) _____ water in their stems and use it very slowly, while others like bushes conserve water by growing few leaves or by having large root systems to gather water or few leaves. Some desert plant species have a short life cycle of a few weeks that (10) _____ only during periods of rain.

(1) _________

• A. 
  coldest
• B. 
  hottest
• C. 
  driest
• D. 
  wettest