单选题：AChristopher Thomas, 27, was a writer by night and a teacher

A
Christopher Thomas, 27, was a writer by night and a teacher by day when he noticed he was always tired and was losing weight fast. Diagnosed with diabetes(糖尿病), Thomas would need to inject himself with insulin(胰岛素) three times a day for the rest of his life or risk nerve damage, blindness, and even death. And if that weren't bad enough, he had no health insurance.
After a month of feeling upset, Thomas decided he'd better find a way to fight back. He left Canton, Michigan for New York, got a job waiting tables, nicknamed himself the Diabetic Rockstar , and created diabeticrockstar.com, a free online community for diabetics and their loved ones—a place where over 1,100 people share personal stories, information, and resources.
Jason Swencki’s son, Kody, was diagnosed with type diabetes at six. Father and son visit the online children's forums(论坛) together most evenings. "Kody gets so excited, writing to kids from all over," says Swencki, one of the site's volunteers. "They know what he's going through, so he doesn't feel alone."
Kody is anything but alone: Diabetes is now the seventh leading cause of death in the United States, with 24 million diagnosed cases. And more people are being diagnosed at younger ages.
These days, Thomas's main focus is his charity（慈善机构）, Fight It, which provides medicines and supplies to people—225 to date—who can't afford a diabetic's huge expenses. Fight-it.org has raised about $23,000—in products and in cash. In May, Thomas will hold the first annual Diabetic Rockstar Festival in the Caribbean.
Even with a staff of 22 volunteers, Thomas often devotes up to 50 hours a week to his cause, while still doing his full-time job waiting tables. "Of the diabetes charities out there, most are putting money into finding a cure," says Bentley Gubar, one of Rockstar's original members. "But Christopher is the only person I know saying people need help now."
Which of the following is true of Christopher Thomas? A．He needs to go to the doctor every day
B．He studies the leading cause of diabetes
C．He has a positive attitude to this disease
D．He encourages diabetics by writing articles