The plants and moons have crashed in the past before but have now settled into a stable orbit
The farmer told the students they were welcome to come back at anytime!
The words in the brackets are telling the actors what to physically do, meaning it would be a stage direction.
It isn't dialogue because that is a conversation between two people.
It isn't dialect because that is how a person speaks. There is no speaking in the brackets.
It isn't narration because it isn't spoken allowed for the audience.
It isn't a description because that is too broad a term more often used for emotions.
The answer to your question is B!!! ;)
