Answer: a

Explanation:
Bona fide is a Latin term meaning in good faith. It’s more often used to mean authentic these days. Bonified is a common misspelling for it — and one that attracts a lot of mockery — but it’s actually a word. Bonify is a somewhat archaic term that means to make something good, especially something that was bad before. Both the bona of bona fide and the bon of bonify come from the Latin word for good, bonus.

Wordnik lists these among mistaken examples of bonified online:

• “At this point, the only thing that will change anything is a bonified miracle of the highest kind.”
  Face It, Progs: Obama’s a Dud « Antiwar.com Blog
• “It amazes me what the art community will accept as bonified art.”
  Situational Taxidermy
• “My father, a 52-year-old bonified curmudgeon, has not viewed any movie trailer in the last ten years with anything other than codified disinterest.”
  2008 June « the balcony fool

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Answer: b.

Explanation:
Infra dig is derived from the Latin infra dignitatem meaning beneath (one’s) dignity.

I feel honor-bound to admit that I’ve never really known what that phrase meant. It came to me in Merriam-Webster’s Word of the Day newsletter — my favorite one (after our own Word of the Day, of course). Here’s their example sentence:

“Among artists lithography was infra dig by the 1870′s — because commercial illustrators had discovered it was a perfect printing medium for glaring posters.” (D. J. R. Bruckner,   The New York Times, December 20, 1998)

In the mood for a little more Latin fun?

See our handy Latin phrase cheat sheet resource.

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