Which layer of the vagina is responsible for lubrication?

The mucosa is the correct answer because it is the innermost layer of the vagina and plays a crucial role in the production of lubrication. This layer contains glandular cells that secrete mucus, which helps to keep the vaginal walls moist and facilitates intercourse. The mucosa also serves as the primary barrier against infections and is involved in the regulation of the vaginal environment.

The submucosa, while it provides support and elasticity to the vaginal walls, does not directly contribute to lubrication. The muscularis layer is primarily involved in the contraction and expansion of the vagina during various activities but does not produce lubrication. Connective tissue provides structural support but does not have a direct role in lubrication either. Therefore, the mucosa stands out as the layer that is specifically responsible for the lubrication of the vagina.