Answer: a

Explanation:
As Bryan Garner, the leading authority on good legal writing (that’s not necessarily an oxymoron) explains, “seldomly” is not a word. Because it is not a word, “seldomly” has no place in writing (which is made up almost entirely of words, after all).

Garner featured “seldom” in a Usage Tip of the Day. “Because this word is an adverb as well as an adjective, the nonword *”seldomly” is never (not merely seldom) needed.”

Garner goes on to quote a couple of examples of “seldomly” from the mainstream press:

o “Hogan was a man so focused that he seldomly [read 'seldom'] noticed what was going on around him.” Jeff Babineau, “Hogan’s Legacy,” Orlando Sentinel, 3 Aug. 1997, at C4.

o “There, one obviously bored soldier checks identifications, and seldomly [read 'seldom'] exercises his prerogative of looking inside bags and purses.” “Deadly Biowarfare Collection Amid Disrepair in Russian Lab,” San Antonio Express-News, 10 Aug. 1997, at A4.

Garner categorizes “seldomly” as Stage 1 on his Language-Change Index:

“Stage 1 (“rejected”): A new form emerges as an innovation (or a dialectal form persists) among a small minority of the language community, perhaps displacing a traditional usage (e.g.: “your” misused for “you’re”).”

Nevertheless, a Google search for “seldomly” turns up 131,000 results, including this Yahoo Answers response:

Top answer: Yes, seldomly [sic] is an english [sic] word. It is used as an adverve [sic].

Adverves! Use more of them to keep your writing lively.

Hahaha. The Prosecution rests, Your Honour.

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