Which one of the following is a membrane that protects the developing embryo from desiccation?

The correct answer is Amnion because it is a thin, tough membrane that surrounds the developing embryo and creates a fluid-filled cavity called the amniotic cavity. This amniotic fluid acts as a shock absorber and provides a moist environment that prevents the embryo from drying out or desiccation. While the other membranes have different roles like gas exchange or nutrient storage, the primary function of the amnion is protection against mechanical injury and dehydration.