Please answer the following question: Read the following article and select the best answer. Article: SHANGHAI, June 7(AP)--A 16-year-old girl's suicide after she was barred from a key exam draw attention to increasing worries over academic pressures, as millions of Chinese students began annual college entrance tests on Wednesday. The three-day exam, viewed as important to future career and financial success, has a record 9.5 million high school students across prefix = st1 /Chinacompeting for just 2.6 million university places. For kids and parents alike, it's a difficulty that experts say causes extreme emotional distress. "Pressure from study and exams is a top reason for psychological problems among Chinese youth," said Jin Wuguan, director of the Youth Psychological Counseling Center at Shanghai'sRuijinHospital. In China's increasingly success oriented, pressure-cooker cities, academic stress is seen as a rising cause of youth suicides and even murders of parents by children who are driven crazy by intolerable pressure to perform. According to her family and newspaper accounts, 16-year-old Wu Wenwen drowned herself after she was stopped at the exam room door because her hair wasn't tied back as her school required. Returning in tied hair, she was then told the end-of-term exam had already started and she was too late to take it. In tears, Wu called her mother, and then disappeared. Her body was found the same night in a nearby lake. China doesn't keep comprehensive statistics on student suicides, but Jin said health care professionals see the problem worsening, even among elementary students. Most Chinese schools still lack advisers and teachers receive little training in spotting symptoms of emotional distress, Jin said. Parents are little help, often piling on pressure while ignoring their children's emotional development, he said. "It's a basic unwillingness or inability to recognize and deal with with emotional problems," Jin said. Wang Yufeng, of Peking University's Institute of Mental, estimates the rate of emotional disorders such as depression among Chinese students under age 17 at up to 32... Question: The 16-year-old girl committed suicide because _ . - she did not tied back her hair as required - she couldn't get high mark in the exam - she had an unpleasant talk with her mother - she wasn't allowed to attend the examination
A:
she wasn't allowed to attend the examination