Scientists have always been interested in the high level of organization in ant societies. American researchers have watched ants build life-saving rafts to keep afloat during floods. They also have documented how ant colonies choose their next queen--the female whose job is to produce eggs rather than seek food for others. New technology is helping to improve researchers' understanding of the insects. But there is still a lot to be learned. Fire ants living in Brazilian forests are perfectly at home in an environment where flooding is common. To save themselves, the insects connect their legs together and create floating rafts. Some ant rafts can be up to 20 centimeters wide. David Hu who is a mechanical engineer with the Georgia Institute of Technology, also known as Georgia Tech, says, "If you have 100 ants, which means 600 legs, 99 percent of those legs will be connected to a neighbor. So they're very, very good at maintaining this network." David Hu and other Georgia Tech researchers want to study ants and the secret of their engineering. They freeze ant rafts and then look at them with the help of computed technology, or CT, images. The pictures show that larger ants serve in central positions to which smaller ants hold. The larger ants form pockets of air that keep the insects afloat. Scientists say small robots or materials that can change shape could be programmed in a similar way, working towards a shared goal. Researchers at North Carolina State University are also studying ants. They examined how Indian jumping ants choose the leader of the colony when they lose their top female or queen. Why did the larger ants serve in central positions in their ant rafts?
To stress their importance. To protect the smaller ants. To attract their enemies. To save their ant societies.
Question: Scientists have always been interested in the high level of organization in ant societies. American researchers have watched ants build life-saving rafts to keep afloat during floods. They also have documented how ant colonies choose their next queen--the female whose job is to produce eggs rather than seek food for others. New technology is helping to improve researchers' understanding of the insects. But there is still a lot to be learned. Fire ants living in Brazilian forests are perfectly at home in an environment where flooding is common. To save themselves, the insects connect their legs together and create floating rafts. Some ant rafts can be up to 20 centimeters wide. David Hu who is a mechanical engineer with the Georgia Institute of Technology, also known as Georgia Tech, says, "If you have 100 ants, which means 600 legs, 99 percent of those legs will be connected to a neighbor. So they're very, very good at maintaining this network." David Hu and other Georgia Tech researchers want to study ants and the secret of their engineering. They freeze ant rafts and then look at them with the help of computed technology, or CT, images. The pictures show that larger ants serve in central positions to which smaller ants hold. The larger ants form pockets of air that keep the insects afloat. Scientists say small robots or materials that can change shape could be programmed in a similar way, working towards a shared goal. Researchers at North Carolina State University are also studying ants. They examined how Indian jumping ants choose the leader of the colony when they lose their top female or queen. Why did the larger ants serve in central positions in their ant rafts?
A. To stress their importance.
B. To protect the smaller ants.
C. To attract their enemies.
D. To save their ant societies.
Answer: