(1) When we call someone “pig” or “swine,” we do not mean it as a compliment. (2) But pigs do not deserve to be used as a symbol for an insult. (3) They are probably not as dirty as they are made out to be. (4) According to one pig keeper, swine are very clean when allowed to live in a clean environment. (5) He feels that pigs are usually dirty simply because their keepers don’t clean their pens. (6) In any case, no one has proven that the pig that wallows in mud prefers that to a cool bath. (7) Furthermore, pigs are smarter than most people think. (8) Many farmers, for example, have observed that pigs frequently undo complicated bolts on gates in search of adventure or romance. (9) So the next time you call someone a pig, perhaps he or she ought to be someone you wish to praise.

Specifically, the major details are

Pigs may be dirty because their pens are dirty; it hasn’t been proved that pigs prefer mud to a cool bath; pigs have been seen undoing complicated bolts.

Pigs are probably not as dirty as people think; pigs are smarter than most people think.

People use “pig” and “swine” as insults; “pig” and “swine” should be considered praise.

Interesting question, because what you are being asked to do is pick out detail that supports an argument. You are not necessarily meant to tell what the argument is.

I think A is the answer.

We learn why they are dirty through no fault of their own.
We learn that pigs can get out of captivity, so they can problem solve.

C is an argument. It is not a detail.

B is a conclusion.

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