A. Protagonist dies of alienation.
B. Protagonist succumbs to the prison of society.
C. Protagonist embodies the author’s misanthropic vision of humanity.
D. Author was drunk.
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NOTE: A may be coupled with D in any era. A will only be coupled with C after WWI. B is rarely coupled with D, but often with C. C and D are frequently coupled. This is especially true of novels written in Continental Europe or by William Faulkner.