Final answer:
The mixer method shortens the mixing and kneading time in yeast bread preparation. It automates these steps for efficiency but does not affect proofing, baking, or ingredient measuring times.
Step-by-step explanation:
When using the mixer method to prepare yeast bread, the area of preparation time that will be shortened is A) Mixing and kneading. This method utilizes a machine to mix the ingredients together and knead the dough, which is not only faster than doing it by hand but also requires less physical effort. It's important to note that while modern methods can speed up this process, they do not reduce the necessary time for proofing or rising, baking time, or ingredient preparation and measuring. In the context of historical breadmaking, this process was lengthy due to reliance on wild yeasts and less precise methods of measuring ingredients.
In contrast, modern yeast strains and precise measurements used in cooking and scientific applications ensure consistency and predictability in the final product. Yeast is particularly useful because it is not fussy about growth conditions and produces carbon dioxide gas which leavens' dough, leading to a light, aerated texture in bread. The mixer method applies these principles efficiently by automating the mechanical steps involved.