The correct answer is C: 90 percent of Iranians are Muslims, of Shia branch. Further 9 % of Iranians are Sunni, which makes 99% of Iranians Muslim! There is also a very small Christian community.
The invention of the transistor in the 1950s allowed engineers to build smaller, faster, and more reliable computers.
This is referred to as the agricultural revolution - option d. It allowed the people to plant their own food (rather than collect) and gave them more security in life. (they could plan ahead and collect food for later).
What how who-Like my comment so i can grow