The correct answer is: B. Weighing accurately, the quantity of each material for a job before mixing.
Batching is the process of weighing and measuring the correct amount of each material to be mixed together to create a desired product. This is an important step in the manufacturing process, as it ensures that the product is of the correct quality and consistency.
Option A is incorrect because it refers to controlling the total quantity of material at each batch. This is not the same as batching, which is the process of weighing and measuring the individual materials.
Option C is incorrect because it refers to controlling the quantity of each material into each batch. This is not the same as batching, which is the process of weighing and measuring the individual materials.
Option D is incorrect because it refers to adjusting the water to be added in each batch according to the moisture content of the materials being mixed in the batch. This is not the same as batching, which is the process of weighing and measuring the individual materials.
In conclusion, the correct answer is: B. Weighing accurately, the quantity of each material for a job before mixing.