Hey there! I'm happy to help!
Most early agricultural societies were located in areas like Mesopotamia (which around Iraq today), so it wasn't very mountainous, so that answer option is incorrect.
Most of these agricultural societies were located in river valleys because you need water to grow crops, so the last answer option is incorrect.
People grew many different crops at this time. It is very unlikely that they all ate the same food. I don't see why farmers would have struggled to vary the crops, so this context doesn't make much sense.
Farmers began to grow better crops, so villagers ate better quality food makes the most sense. Agriculture yields good, natural food, so the villagers will be eating better quality food because the agricultural civilization was advancing.
Have a wonderful day! :D
