You can replace "out of their control" with "almost zero chance to go in the else{} branch". And "can choose to" with "can go to else{} if rx is true" - and so

You can replace "out of their control" with "almost zero chance to go in the else{} branch". And "can choose to" with "can go to else{} if rx is true" - and social interaction and reward/punishment can make rx == true.