D.
Honestly, 3 to 4 ozs is alot. You have to remember that their tummy's are only the size of their fist. Don't force feed them. When they refuse the bottle it means their full and stop. My 7 mo old will only eat 4 oz or so at a time and goes 4 or so hours between feedings. Don't worry about how many oz their eating, and if their not finishing bottles. Their eating just fine and when they are full they'll stop eating. As long as they continue to gain weight their perfectly healthy.