阅读下列三篇材料，从每题所给的A、B、C和D四个选项中，选出最佳选项，With devices (设备) that can be conveniently (便利地) controlled from anywhere, a smart home offers convenience to its owners. These devices can be connected with each other through the Internet, allowing the user to control functions, such as security access (安全访问), lighting and temperature.
"Haitangxiaozhen", an Internet user from Xuzhou, Jiangsu, shared his experience of setting up a smart home. He first bought the service of "intelligent networking". It can be extended (延伸) to every room. He then can use an app to control various smart home devices.
He said that he usually got off work late, ____. But now, cooked rice waits for him at home because he can turn on the rice cooker with his phone in advance. During summer, he usually turns on the air conditioner 30 minutes before getting home. He can also check the security camera at the door anytime through his phone in case he forgets whether he has locked the door or not. It's very convenient for him.
During winter and summer holidays, when his child was alone at home, he used to worry about safety problems. For this reason, he specially installed a smart camera. With it, he can check if his child is OK at any time. His home also has a kitchen safety set, including smoke sensors (传感器), gas sensors and water sensors.
And these devices are really smart. They come with self-learning skills so they can learn the home owner's timetables and make changes as needed.
All these conveniences are making smart homes more and more popular both in China and around the world.
"Smart homes are not yet perfect. They also bring problems. Every device has its own app, leading to a large number of apps for me to deal with." another user said.
