Đáp án đúng: B
Giải chi tiết:\(\begin{array}{l}375:\left( {x - 3} \right) = 12\\\,\,\,\,\,\,\,\,\,\,\,\,\,x - 3\,\,\, = \,375:12\\\,\,\,\,\,\,\,\,\,\,\,\,\,x - 3\,\,\, = \,31,25\\\,\,\,\,\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\,\,\, = \,\,31,25 + 3\\\,\,\,\,\,\,\,\,\,\,\,\,\,x\,\,\,\,\,\,\,\,\,\, = \,\,\,\,\,\,34,25\,\,\,\,\,\,\,\,\,\,\,\,\,\end{array}\)
Chọn B.