Is it permissible for a father to refuse his son's engagement to a girl merely because she is from a different geographical region, and is the son obligated to obey his parents in this refusal?

The obedience to parents in their prohibition of marriage to a specific woman is confirmed if they have a valid reason, such as fear for their son of drifting away. It is advised to agree with the parents, and Allah will compensate with something better than what was forsaken to please them.