Answer: a.

Explanation:
To augur is to indicate or predict from signs or omens; augury is the practice of doing so. An auger, on the other hand, is a type of device used to drill holes.

In ancient Rome, an augur was a priest who foretold events by interpreting natural phenomena, such as the entrails of sacrificial birds. (I had to hold myself back from saying “foretold future events” but, really, what other kind could you foretell?)

There are a couple of theories about where the word came from. One is that it derives from an Old Latin (There’s my thing learned for today — there was Old Latin before the Latin that we think of as pretty old itself) word for increase because augury was often used to predict the likelihood of crop increases. (That’s where the word augment comes from.) The other theory is that augur comes from avi and geros, meaning “directing the birds.”

The interesting thing about auger is that it used to be nauger but somehow a nauger was split up incorrectly as an auger. That’s just one of many entertaining facts in @EditorMark’s Twitter Archive.

The nauger reminds me of a joke about a nobby in Cathleen Schine’s The Three Weissmans of Westport. Which I think I’m going to have to post about separately because I’ve gotten sidetracked enough for one post.

There’s more information about augurs and augury in the Wikipedia entry.

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