People are more likely to wash their hands properly after using the toilet if they are shamed into it or think they are being watched, scientists said on Thursday. Hand-washing is the cheapest way of controlling disease but less than one third of men and two thirds of women wash their hands with soap after going to the toilet, a British study by the London School of Hygiene and Tropical Medicine showed. But when prompted by an electronic message flashing up on a board asking: "Is the person next to you washing with soap?," around 12 percent more men and 11 percent more women used soap. Health authorities around the world are stepping up efforts to persuade people to be more hygienic and wash their hands properly to help slow the spread of H1N1 swine flu, which was declared a pandemic  by the World Health Organization in June. "Hand-washing with soap has been ranked the most effective way for the worldwide control of disease," the study's authors wrote. "It could save more than a million lives a year from diarrhoeal diseases, and prevent respiratory  infections -- the biggest causes of child mortality  in developing countries." In developed nations, hand-washing can help prevent the spread of viral infections like flu and sickness and diarrhea bugs like norovirus and rotavirus, as well as hospital-acquired infections like MRSA and C-difficile, the authors said. The researchers studied the behavior of a quarter of a million people using toilets at motorway service stations in Britain over 32 days.Use of soap was monitored by sensors. The study, published in the American Journal of Public Health to mark Global Hand-washing Day, showed that with no reminders, 32 percent of men and 64 percent of women used soap. In which of the following situation can people wash their hands properly?
After they going to toilet. when they think they are being watched. When they think their hands are dirty. When they find soap nearby.
Question: People are more likely to wash their hands properly after using the toilet if they are shamed into it or think they are being watched, scientists said on Thursday. Hand-washing is the cheapest way of controlling disease but less than one third of men and two thirds of women wash their hands with soap after going to the toilet, a British study by the London School of Hygiene and Tropical Medicine showed. But when prompted by an electronic message flashing up on a board asking: "Is the person next to you washing with soap?," around 12 percent more men and 11 percent more women used soap. Health authorities around the world are stepping up efforts to persuade people to be more hygienic and wash their hands properly to help slow the spread of H1N1 swine flu, which was declared a pandemic  by the World Health Organization in June. "Hand-washing with soap has been ranked the most effective way for the worldwide control of disease," the study's authors wrote. "It could save more than a million lives a year from diarrhoeal diseases, and prevent respiratory  infections -- the biggest causes of child mortality  in developing countries." In developed nations, hand-washing can help prevent the spread of viral infections like flu and sickness and diarrhea bugs like norovirus and rotavirus, as well as hospital-acquired infections like MRSA and C-difficile, the authors said. The researchers studied the behavior of a quarter of a million people using toilets at motorway service stations in Britain over 32 days.Use of soap was monitored by sensors. The study, published in the American Journal of Public Health to mark Global Hand-washing Day, showed that with no reminders, 32 percent of men and 64 percent of women used soap. In which of the following situation can people wash their hands properly?
A. After they going to toilet.
B. when they think they are being watched.
C. When they think their hands are dirty.
D. When they find soap nearby.
Answer: