SC guide 4th edition CH 10 problem set Q1

[coolacl]

is the usage "accelerating decline of sales of compact disks" correct? should it not be "accelerating decline in sales of compact disks"?

[esledge]

hmm, "decline in sales" sounds better to me, too. But that doesn't necessarily mean "decline of sales" is outright wrong. If the GMAT offered two choices that were identical but for decline in/decline of, I'd say "go with your ear." But there are many idioms that the GMAT considers too close to call, and this might be one of them.

Our idiom glossary in the SC guide is based on the idioms known to be tested by the GMAT, and "declined" is not among them.