The correct options are
A Heavy, clayey soil could be turned over better.
B More grain could be produced.
C It enhanced agricultural technology.
There were few major changes in agriculture during the Vedic period. One of them was the shift from use of wooden ploughshares to iron ploughshares. Wooden ploughshares pushed soil to either side and did not result in inversion. Iron ploughshares could turn heavy, clayey soil better and this resulted in enhanced agricultural technology which led to increase in grain production.