Which of the following sentences is correct?
AI stayed up all night doing homework; however, I just couldn't concentrate.
BI stayed up all night doing homework, however I just couldn't concentrate.
CI stayed up all night doing homework however, I just couldn't concentrate.
DI stayed up all night doing homework, however. I just couldn't concentrate.
AI stayed up all night doing homework; however, I just couldn't concentrate.
BI stayed up all night doing homework, however I just couldn't concentrate.
CI stayed up all night doing homework however, I just couldn't concentrate.
DI stayed up all night doing homework, however. I just couldn't concentrate.