Given:
The given balanced scale is represented by the equation
----- (1)
We need to determine the process that balance the scale.
Process to balance the scale:
Given that the if one x block is subtracted from the right side and three numbered blocks are subtracted from the left side.
Thus, the equation (1) becomes

----- (2)
Now, to balance the scale, let us subtract one block x from the left side and subtract three numbered blocks from the right side.
Thus, the equation (2) becomes,

------ (3)
Thus, the equation (3) is the same as the equation (1).
Hence, the process required to balance the scale is to subtract one x block from the left side and subtract three numbered blocks from the right side.
Therefore, Option B is the correct answer.