commerce depart

Received a PM asking me to explain why D is wrong. I'm curious - where did this problem come from?

There's something of a clarity of meaning issue here. We could also call it "that's just the way we say it in English," which is not very GMAT-like. This doesn't seem like a very well-written problem to me.

First, clarity of meaning:

Something went down when it might have been expected to go up. When you phrase it this way, it's very clear that the "went down" and "to go up" (both forms of verbs) both apply to the original subject, "something."
"inflation eased (an action) when it (inflation) might have been expected to rise (an alternate action)"

In D, "rise" is a noun, not a verb, which is the first thing that muddles the meaning. The rise of what? What rose or could have been expected to rise? We have a pronoun beforehand: its. So "its rise" - what does "its" refer to? Probably inflation. But it doesn't have the nice parallelism that choice B has, so B is better than D.

But, again, it's not very GMAT-like to have to rely on that reasoning to get to the answer. The test-writers are interested in knowing whether you know the grammar, not whether you know how native speakers would prefer to word something.

Personally, I wouldn't study this one.

Does this question not show up in either OG11 or OG12? A couple of years ago, GMAC said at a meeting that they were trying to eliminate verbal questions that gave a clear advantage to native speakers - content that would more likely be known by native speakers, which includes more obscure things for which we'd say "that's just the way we prefer to say it in English." So I'm guessing that this one has not been used after OG10 and this is why.

Note that we are talking about an idiomatic construction here but this is different than idioms for which we can set a simple, definitive rule (use this preposition after this word, etc.). The "simpler" idioms are ones which non-native speakers can be expected to learn. The more complex ones, where entire clauses are written a certain way "just because" - that starts to introduce a bias in favor of the native speakers.