Final answer:
The structure of the sentence provides insight into Quentin's character and makes his action more believable.
Step-by-step explanation:
The effect most clearly created by the structure of the given sentence is option B. It adds detail to provide insight into Quentin's character to make his action more believable. The sentence includes multiple descriptive phrases and clauses that provide information about Quentin's personality (timid, afraid of his own shadow) and his actions (stood up to defend his younger brother when he was threatened by a bully). This additional detail deepens our understanding of Quentin's motivations and choices.
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