Final answer:
The correct punctuation for the slang term for jail in the given sentence is 'jail—hoosegow—', which uses em dashes as per option (b).
Step-by-step explanation:
The correct option for the punctuation of the sentence regarding the slang word for jail is option (b) jail—hoosegow— as it correctly sets off the slang term with em dashes, indicating an appositive or an aside that provides additional information on the word 'jail.' The sentence, if correctly punctuated, would read: 'The funny slang word for jail—hoosegow— was a garbled version of the Spanish word for "courtroom," juzgado (pronounced /hooz-GAH-doh/).'