in the 1800s and first mass-produced in Germany, the harmonica(口琴) was designed to play simple folk tunes.
A. Being invented
B. Inventing
C. Invented
D. Having invented
网友回答
A. Being invented
B. Inventing
(答案→)C. Invented
D. Having invented
解析：考查非谓语动词。逻辑主语the harmonica与invent之间为被动关系，故用过去分，选C。