Today, social media has become an essential part of an individual's life. From reading about current events to discussing a TV show's latest episode with friends, everything is now done on social media. A few years ago, only a handful of social media sites existed, which people hardly used. Now, the Internet is cluttered with social media sites ranging from those that let people share photos and videos to those that allow people to broadcast their thoughts and experiences live.
Today, social networking sites are very popular. This is because a large number of people have accounts on all social media sites, and they are usually online throughout the day. According to a survey conducted by a research center, 94% of teens use cellphones to go online at least once daily in America. Further, this research center concludes that around 56% of these teens go online several times a day. Most teens spend time online browsing through social media sites, reading people's posts or looking at pictures and watching videos.
One of the positive aspects of teens spending more time on social media is that they can be contacted at any time of the day. Modern educators are interested in integrating social media in classroom learning. Students can get in touch with teachers anytime if they are inquisitive about a certain topic or have questions about what they recently learned in the classroom. This also helps teachers know that students are interested and have been paying attention in the classroom. Teachers can create a group on social media and add their students to the group. They can post links and videos for their students and encourage them to share their observations with others. In this way, the entire class can view information with a single click. This can ensure that students are prepared for a class beforehand and that teachers do not have to restate the same information.
Social media can help students contact each other when they need help. Class projects, group assignments, or homework-related inquiries can be easily resolved on social media groups. Social media can also help parents keep track of their child's progress at school. Since classrooms are being modernized by combining technology with traditional resources, social media should be considered as a practical tool to educate students and spread knowledge.

1. Based on the passage, which event has most directly influenced the increase in popularity of social media sites?
A.
the change in the way people use their cellphones for entertainment
B.
the increase in the total number of teachers who are adopting social media sites for classroom instruction
C.
the change in the preferred method of receiving an online education
D.
the increase in the total number of people who are active on social media sites throughout the day