The nervous-looking young man had waited for a few moments--outside the jeweler's before he got enough courage to enter. He was warmly greeted by a young assistant. James felt a rush of blood to his face as he explained he would be bringing in his future wife to choose a birthday present. The assistant listened carefully and told him he'd better buy a necklace. He wasn't used to buying jewellery and was a little worried about over-spending. After some discussion as to a reasonable price and the type, the assistant showed him dozens of necklaces and helped him to choose. At last James chose one and left the shop promising to return at five o'clock. When, half an hour later than planned, James did return to the shop with his future wife, Laura, the assistant acted as if she had never seen him before. When she was asked to show them some necklaces, she first brought out some inexpensive ones for them to choose, and then gave them the one she had prepared. A choice was soon made and they went away satisfied. James would certainly come back to buy what he wanted. James would come back to buy what he wanted because  _  .
the assistant knew how to satisfy the people who came to buy things the necklace was good Laura liked the necklace the assistant who served James was very beautiful