Puppy growling

We have a 4 month old puppy that has been growling when he's unhappy with something. Examples: 1) when we try to physically move him, whether he's in our way or we are trying to get him up in the morning. 2) If we try to take his bully stick away from him

We have him in puppy training classes 2x a week and daycare 1x a week in which he's shown no aggression or issues with other dogs. The trainer basically told us that this is somewhat natural behavior for a puppy. She recommended that in an instance of him not moving, to offer a treat to lure him up, or to get him distracted from the bully stick with a different treat and then take it away. I feel this isn't really addressing the issue. Any experience with this or suggestions? TIA