Sometimes I think how grateful I would be today if I had learned more back then about what really matters.

Sometimes I think how grateful I would be today if I had learned more back then about what really matters.
A、Sometimes I feel happy that I was taught what is important at school.
B、Sometimes I feel sorry that I didn"t learn what is important at school.
C、At times I feel resentful that I was not taught anything useful at school.
D、At times I feel I should be thankful for those things I learned at school.
正确答案：B