The young man in studying paid no attention to the outside world.
A. involved
B. involving
C. to be involved
D. being involved
网友回答
A. involved
B. involving
C. to be involved
(答案→)D. being involved
解析：考查非谓语动词。be involved in全神贯注于。在句中作定语，相当于定语从句，who is involved in，who is 省略。句意：专注于学习的那个年轻人没有注意到外面发生了什么。