D.
Try soothing him without picking him up. Rub his tummy or back and shhhhhh's him. The more you distrupt him the harder it will be for him to learn to do this on his own. But leave him in the crib. My daughter does this too. All I have to do is go in, replace the binky turn her music back on and leave the room. I play soothing music in my kids rooms while they sleep, if they wake it helps them get back to sleep very quickly. Lullabies and classical. It helps set the mood for sleep. So I'd start doing that maybe, this way when he hears the music he will know where he is. And he can start to learn to sooth himself, which is your goal.