Correct Option: C
The given polynomial $x^3+x+1$ is written as 1011, which consists of 4 bits so, append 3 bits of 0s to the message.
$M= 11000000$
$$\begin{array}{l} 1011\overline{\smash{)}11000000}\\ \phantom{1011\smash{)}}\underline{1011}\\ \phantom{{x-31}}1110\\ \phantom{{1011\smash{)}1}}\underline{1011}\\ \phantom{1011\smash{)11}}{1010}\\ \phantom{1011\smash{)}11}\underline{1011}\\ \phantom{1011\smash{)}11111}{100}\\ \end{array}$$ There the check bits sequence is: 100.