The most useful advantage of adding a vegetarian hot-food option to a school lunch menu is
limiting the amount of food that is wasted by the school.
presenting an additional choice for teachers and staff.
providing an additional choice for students on restricted diets.
reducing the cost of lunch options for students and teachers.

the correct answer is the following is a list of inventions made in the medieval islamic world, especially during the "islamic golden age" (8th to 13th centuries),[1][2] as well as the late medieval period, especially in the emirate of granada and the ottoman empire.

science and technology in the islamic world adopted and preserved knowledge and technologies from contemporary and earlier civilizations, including persia, india, china, and greece-roman antiquity, while making a number of improvements and innovations.