A、He suffers from a blocked nose. B、He suffers from a leaky nose. C、He suffers from a cough. D、All of the above. D从文章一开头就提到了一位母亲

A mother in Tamil Nadu, India, recently had a question for our new series on children and parenting. This woman in Tuticorin has a son who is almost three years old. He attends a pre-kindergarten school. (26) She wonders why he often suffers from a blocked or leaky nose and a cough. Along with these, he gets a temperature of thirty-eight and three-tenths degrees Celsius.
    Children can come in contact with all sorts of bacteria, viruses and other organisms as they share toys, toilets and towels. Some will make them sick, others are harmless.
    (27) Good hand washing is an important way to reduce the spread of infections. Caregivers should also be trained in ways to clean, sanitize and disinfect. The Web site for the National Resource Center for Health and Safety in Child Care explains the differences.
    This  government-financed  center  says  parents should look around child care centers.  Make sure toys, furniture and other equipment are clean and in good condition. Not only that, ask how often things get cleaned—there should be an established program.
    The experts in Colorado say parents should not take sick children to day care if they might infect others. They also advise child care operators to keep a sick child away from healthy children whenever possible.
    Being in a "germ factory" is not necessarily all bad. (28) Some experts believe that children exposed early to common germs develop a greater resistance to them when they reach school age.
26. What does the son suffer from?
27.Why is good hand washing important?
28.According to some experts what’s the benefit for children exposed early to common germs?