During the golden age of the Islamic empire, many advancements were made in lots of different areas. New forms of art were created, and new ways of thinking, including the beginnings of the mathematic system of algebra, emerged as well. So it's A.
I would say "women", although that seems a little simplistic.
People should become vegetarian because it is proven to be healthier and besides we should have compassion for animals; since there is way too much animal cruelty going around just to have a plate of meat on the table.
By conserving the natural resources and replenishing the renewable ones and limiting the non-renewable ones.