Owls  are mysterious creatures. We often think of them as scary. They sometimes live in abandoned houses. They fly without a sound through backyards at night. In stories, they appear with ghosts. When we hear an owl's familiar "whooo...whooo...",it can make us feel very frightened. Owls fly silently, without even a whisper of wings moving through the air. It's as though they appear out of nowhere--like ghosts on wings. Owls fly and hunt on the darkest of nights. An owl's night habits make it unique. Do these creatures of the night possess strange powers? Owls possess unusual powers of sight and hearing, but they are not supernatural powers. They are natural adaptations that let them live most efficiently  at night. There is no reason to fear owls. Their habits make them helpful to humans. By hunting mice and other rodents ,owls help to keep a natural balance between plant and animal life. Without owls, there would be a large number of rodents in farmers' fields and storage barns. More than 100 species of owls occupy a variety of habitats around the world. A few oceanic islands and the Antarctic have no owls. The world's owls come in large, medium, small, smaller, and smallest. For example, the Eurasian eagle owl--one of the largest--has a body that is two to three feet long, with a wingspan  of up to five and onehalf feet. The North American elf owl (the world's smallest owl) is five to six inches long and has a wingspan that measures slightly more than one foot. Most male and female owls of the same species look alike, although females are usually larger. In some species, the female's colors are like those of the trees or grass where she makes her nest. Baby owls, called chicks, stay with their parents until they are about three months old. They soon find their own hunting areas, where they may stay for the rest of their lives. Some owls can live 20 years or more. Owls help humans in that they  _  .
help preserve the balance of nature frighten rodents away from humans have unusual powers help guard backyards
Question: Owls  are mysterious creatures. We often think of them as scary. They sometimes live in abandoned houses. They fly without a sound through backyards at night. In stories, they appear with ghosts. When we hear an owl's familiar "whooo...whooo...",it can make us feel very frightened. Owls fly silently, without even a whisper of wings moving through the air. It's as though they appear out of nowhere--like ghosts on wings. Owls fly and hunt on the darkest of nights. An owl's night habits make it unique. Do these creatures of the night possess strange powers? Owls possess unusual powers of sight and hearing, but they are not supernatural powers. They are natural adaptations that let them live most efficiently  at night. There is no reason to fear owls. Their habits make them helpful to humans. By hunting mice and other rodents ,owls help to keep a natural balance between plant and animal life. Without owls, there would be a large number of rodents in farmers' fields and storage barns. More than 100 species of owls occupy a variety of habitats around the world. A few oceanic islands and the Antarctic have no owls. The world's owls come in large, medium, small, smaller, and smallest. For example, the Eurasian eagle owl--one of the largest--has a body that is two to three feet long, with a wingspan  of up to five and onehalf feet. The North American elf owl (the world's smallest owl) is five to six inches long and has a wingspan that measures slightly more than one foot. Most male and female owls of the same species look alike, although females are usually larger. In some species, the female's colors are like those of the trees or grass where she makes her nest. Baby owls, called chicks, stay with their parents until they are about three months old. They soon find their own hunting areas, where they may stay for the rest of their lives. Some owls can live 20 years or more. Owls help humans in that they  _  .
A. help preserve the balance of nature
B. frighten rodents away from humans
C. have unusual powers
D. help guard backyards
Answer: