单选题：根据下面材料，回答题：A man from New York is suing four big fast-food

根据下面材料，回答题：
A man from New York is suing four big fast-food companies. Caesar Barber is going to court be-cause he says that high-fat foods at McDonald's, Burger King, Wendy's, and KFC Corporation destroyed his health. Barber says that he ate at these restaurants four or five times a week for many years. He claims that this diet made him very overweight. According to Mr. Barber, obesity(肥胖症) gave himdiabetes (糖尿病), high blood pressure, and two heart attacks. When a reporter asked him why he ate there so often, he said, "I was single, it was quick, and I'm not a very good cook. "
Barber's lawyer, Samuel Hirsch, says that the suit has two different purposes. The first is to makefast-food restaurants offer healthier foods in smaller amounts. The suit also asks that fast foods have warning labels similar to labels on cigarettes. Mr. Hirsch says that these labels are necessary because the effects of fast foods are similar to the effects of cigarettes, alcohol, and illegal drugs such as heroin. Two others may soon join Barber's suit. One is Frances Winn, a 57-year-old retired nurse. Ms.Winn says that she has eaten at fast-food restaurants at least twice a week since 1975. She says that this habit has caused several health problems, including high blood pressure. Is real Bradley,59, said eating a pound of French fries every week gave him high blood pressure and diabetes.
Officials of the fast-food industry attacked the legal action. National Restaurant Association representative Katharine Kim called it ridiculous. KFC spokeswoman Amy Sherwood claimed KFC offers several kinds of foods for people who want to eat healthier. Legal expert Walter Olson agreed that the suit had litle chance of success. He said that people were free to make different choices.
Whether or not the suit is successful, there is no doubt that Americans have a weight problem. Medical experts say that obesity will soon be America's number one killer. They have encouraged fast-food companies to offer healthier foods.
What does the word" suing" in the first sentence mean? A．Attacking.
B．Mentioning.
C．Complaining about.
D．Taking a legal action against.