第 1 题：单选题:
He finally achieved success after a lot of failures.
第 2 题：单选题:
He is so happy to find a girl with a shared interest with him.
第 3 题：单选题:
He doesn't know which one is the best in all of these options.
第 4 题：单选题:
They didn't realize how serious the problem was.
第 5 题：单选题:
Many students today display a disturbing willingness to choose their careers.