Cathy and Louise want a picture of their children and the children do what they are told because they know what is good for them . Erica and Johnny show up to take one last rip and all of a sudden it is over . The trip is complete , Ian and John drop off the crew at Britannia Yacht Harbour and go and pull the boat out .

Question: What may have been reason behind the statement " they knew what is good for them ? "
Answer: The children always did the right thing because they knew their parents would give them a wonderful treat later .The children were trained to be mechanical because their parents loved them and wanted them to be perfect .None of the above choices .The kids were aware of the fact that they would be punished if they did n't what they were ordered to do .