阅读下面短文，从每小题A、B、C、D四个选项中，选出能回答所提问题的最佳答案。
D
Inventions make our life easier and better than before. What are the best inventions of last year? Here are three amazing things in Time magazines list of the 25 best inventions of 2017.
Smart mug
It's hard to keep coffee or tea warm, especially in winter. But this smart mug from US company Ember Technologies can solve this problem. There is an app for the mug that allows people to set the mug to a certain temperature between 48℃ and 62℃. Then, the mug keeps your coffee or tea at that temperature for about an hour, and even longer if you put the mug on a charging（充电）plate.
Social robot
Can robots talk to us like humans? Jibo, a robot made by US company Jibo Inc, can do this. With a big, round head and a big body, Jibo looks like a cartoon character. And its voice sounds like a 10-year-old boy. As soon as you say "Hey, Jibo," it dances and turns to face you. When it talks to you, it moves its head and body to communicate with you. Its appearance, tone of voice and humor make you feel that you have a little friend Jibo is able to tell stories to children, take pictures just by hearing your order "Jibo, take a picture", and do hundreds of other jobs. Although its creators think that Jibo still has a lot to learn, it's available with a price of $ 899; a good price for a pretty smart and friendly robot!
Fidget spinner
What is the most popular toy this year? The answer is probably fidget spinners. They are small plastic or metal toys with a bearing(滚珠轴承）in the middle. The toys can keep turning around on your fingertip for a few minutes after you start them. Once they are turning, you can put them on any other flat surface, such as a ruler or even the nose of a pet dog. This toy is very popular among young people around the world. Some people say that it helps them calm down and relax. But it may not be a good thing to spend too much time playing with it.
