Yield your Ground doesn't trigger by attacks. It triggers by movement.
So, you can't interrupt attacks with it.
If they'd triggered their readies by attacks, you'd have moved away when the third one moved close. In this case, however, their readied action is not lost, so they can still use it if it triggers.
If they'd triggered their readies by movement, you chose to ignore movement A and B. In this case, the DM adjudicates what the order is. Not sure how I'd adjudicate this. But either way, you'd not be able to negate any attacks with this, their readied actions would still be valid. And based on what the readied action's trigger is, they might attack someone else in range. 'When an enemy is in range, and Charlie is in position' is a valid trigger, and wouldn't be wasted if you moved away when Charlie enters position.