What am I suppose to do in this position

So after c5 I have plenty of options either I should have played bf3 or push my knight to d5. Me personally I forgot the logic but the engine told me to play nxa6. Why nxa6 is a good move for white?

So after c5 I have plenty of options either I should have played bf3 or push my knight to d5. Me personally I forgot the logic but the engine told me to play nxa6. Why nxa6 is a good move for white?