What does the term "marrying liquor" refer to?

The term "marrying liquor" specifically refers to the process of pouring liquor from one bottle to another, which often occurs to mix different batches of spirits for consistency or to enhance the overall quality of the product. This technique is commonly used in the production of liquors, where producers may combine several barrels or bottles to achieve a desired flavor profile or to ensure uniformity across a product line.

While the other options might seem related to the general concept of mixing or serving drinks, they don't capture the specific meaning associated with "marrying liquor." Mixing different cocktails is more about creating distinct beverages, serving drinks in pairs refers to the presentation or serving style, and blending liquors for flavor implies a temporary mixing for a specific drink rather than the more established process of combining different productions of spirits. Thus, the most accurate definition of "marrying liquor" aligns with the careful transfer of liquor between containers to achieve a uniform and balanced product.