I just wanted to chime in and say that my ds6 would choose the easy option too so that he could finish more quickly. Afterward, he'd complain that it was too easy. One day I asked him to make a choice similar to what you are describing. He chose the easier option, and I said, "you know, later you are going to complain that this was too easy." That's when ds6 said, "It seems like an adult decision to me." And, he was right.