Critical Reasoning: Mr. and Mrs.  Chowdhury and their son Babul want to cross a river. The only way across is with Mr. Rahman in his rowboat. Mr. Rahman will not allow any one to row his boat and will take only one passenger at a time. Babul is only little boy so  he cannot be left alone on the riverbank. Which of the following conditions are not pats of the passage on the river crossing of the Chowdhurys?