What is the primary text structure of the passage below?

Since the contrivance of smartphones, the world has become a better place. Now, a person is able to communicate with their family, friends, and anyone in the world at virtually any time. Due to this, we can learn more from others than ever before. Now, emergency situations are much more easily dealt with, and help can be on the way almost instantly. Because we now have smartphones, entertainment is at our fingertips. Connecting through social media, watching a favorite program, or consulting for information is as easy as pressing a button on one’s phone. With the invention of smartphones, humans were ushered into the digital age completely.

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A) Cause and effect
B) Problem/solution
C) Description
D) Compare and contrast