【正确答案】
C
【答案解析】[听力原文] China, which has long had a goal of breaking into the Western-dominated aircraft market, on Friday tested its first large passenger jetliner. The C919, made by state-owned Commercial Aircraft Corp. of China Ltd., or Comac, took off from Pudong International Airport in Shanghai. The new plane is expected to compete with the Airbus A320 and Boeing's 737. The lucrative narrow-body market accounts for more than 50 percent of the aircraft in service worldwide. The C919 has been beset by delays: It was expected to first fly in 2014 and be delivered to buyers in 2016. Comac officials blamed the delays on manufacturing problems, but they are looking forward to a brighter future. Over the next 20 years, the global jet market is estimated to be worth $2 trillion. China's new jet, however, likely faces a lengthy journey from first flight to commercial usage. A similar thing happened to China's first domestically made jet. The twin-engine ARJ-21, flew its passengers in June 2016, eight years after its first test flight. What did Comac officials blame for the delay of the test flight?