阅读下列短文：从每题所给的A、B、C、D四个选项中，选出最佳选项，将正确的选项涂在答题卡上。
A
Dear Alfred，
I want to tell you how important your help is to my life.
Growing up, I had people telling me I was too slow, though, with an IQ of 150 at 17, I’m anything but stupid. The fact was that I was found to have ADIID(注意力缺陷多动障碍). Anxious all the time, I was unable to keep focused for more than an hour at a time.
However, when something did interest me, I could become absorbed. In high school, I became curious about the computer, and built my first website. Moreover, I completed the senior course of Computer Basics, plus five relevant pre-college courses.
While I was exploring my curiosity, my disease got worse. I wanted to go to college after high school, but couldn’t . So, I was killing my time at home until June 2012 when I discovered the online computer courses of your training center.
Since then, I have taken courses like Data Science and Advanced Mathematics. Currently, I’m learning your Probability course. I have hundreds of printer paper, covered in self-written notes from your video. This has given me a purpose.
Last year, I spent all my time looking for a job where, without dealing with the public , I could work alone, but still have a team to talk to. Luckily, I discovered the job—Data Analyst—this month and have been going full steam ahead. I want to prove that I can teach myself a respectful profession, without going to college, and be just as good as, if not better than, my competitors.
Thank you. You’ve given me hope that I can follow my heart. For the first time, I feel good about myself because I’m doing something, not because someone told me I was doing good. I feel whole.
This is why you’re saving my life.
Yours,
Tanis
why did’t Tanis go to college after high school?（）
A.She had learned enough about computer science
B.She had more difficulty keeping foucesed
C.She preferred taking online courses
D.She was too slow to learn
