Money and the economy may cause stress because we have to devote a lot of brain power to making financial decisions, whether it's thinking about paying the mortgage, buying groceries, or saving money. These financial decisions, big or small, require willpower.Willpower is like a muscle that can become tired and lose strength when overused.1. Why may money and the economy cause stress?A. People have to find ways to make enough money.B. People have to use brain power to make financial decisions.C. People have to think about paying the mortgage.D. People have to save as much money as possible.