Oracle Database 11g: Performance Tuning

I am a college teacher, I am so proud of my position, my job, because of my naughty guys, they were very activity at school, they took part in all things organized by institute, academy... and won a lot award! It made me very proud! But for this, they worked very hard on their studies, they almost passed all the exams in the four years, we were always the No.1 in our college, I also got such many award!
You work as a DBA for a company and you have the responsibility of managing one of its online transaction processing (OLTP) systems. The database encountered performance-related problems and you generated an Automatic Workload Repository (AWR) report to investigate it further. View the Exhibits and examine the AWR report.

What could be the problem in this database?

A.Java pool is not configured.

B.The CPU in the system is slow.

C.The shared pool size is inadequate.

D.The database buffer cache is inadequate.

E.The OPEN_CURSORS parameter is set to a small value.

ANSWER: C
However, time flies, it's time to say goodbye to our happy time! Maybe this is the last day I can stay with all my students, tomorrow, they will out to the society working for their future! Four years have passed, it’s really a long time for such a middle-aged women like me! It took my four years time to stay with these lovely students, all things come to me at this moment!
Still remember that half a year ago, one of my student John came to ask me whether it’s good to take some IT certifications such as 1Z0-054 study guide, then we had a half-day discussion with all my class! To my surprise, half of them decided to take the IT exams of Oracle 1Z0-054 Oracle Database 11g: Performance Tuning, I began to worry about their passing rate till a day they came to tell me that there is no need to worry about that! I was wondering what made them so confident. But they said, it's just a surprise for me!