$\text{Bit-Stuffing}:$ Bits stuffing is the insertion of noninformation bits into data and it is used for synchronization purpose example
$A. 0111110100 \rightarrow 011111\color{red}{0}0100$
$B. 0111110101 \rightarrow 011111\color{red}{0}0101$
$C. 0111111101 \rightarrow 011111\color{red}{0}1101$
$C. 0111111111 \rightarrow 011111\color{red}{0}1111$
So Option $B$