Answer:
A). Inner Ear.
Explanation:
In paragraph 7 of the passage, the word 'inner ear' is a pattern transition as it assists the readers to understand the key focus of the author i.e. 'to aware the readers about the role of hair cells(present in the inner ear) in one's ability to hear.' It helps the readers to follow the author's claim regarding the significance of these cells and how exposure to excessively loud music leads to destruction of these cells and consequently, despairs the hearing ability. Thus, the pattern transition 'inner ear' helps the readers know that the author is concerned about damaging of hearing ability and thus, explains how it is affected to aware the readers about it.
They are collaboraters or colleagues because they work together<span />
