Answer:
Letter B - India/Pakistan
Explanation:
The venue of the Green Revolution in India allowed to prevent a massive famine in India and Pakistan in the early 1960's, saving a great number of people in this second most populated country of the world.
A Mexican research team introduced a new variety of wheat in India during that period and that earned them a Nobel Prize in 1970.
I think it is Christianity
El Salvador. Hope this helps!

subtract 8 from both sides leaving

combine -2x+-8x =-10x

divide both sides by ten