Answer:
The organizational pattern being used is A. definition.
Step-by-step explanation:
This question is confusing to many people - you will actually find several claiming the answer is letter C, classification, which it is NOT. As a matter of fact, we just need to take a look at the beginning of the excerpt to identify the pattern.
The author says, "Gravity is the source of a black hole’s super pull." What is she doing here? She is defining gravity, explaining what it is, its meaning. The rest of the excerpt is a continuation of that pattern. She is offering further details to make the definition more complete. A definition pattern is easily identifiable because it often uses terms such as: is, means, refers to, is called, is defined as, entails, is characterized by.