Ok kids here's my reasoning so I may be able to shed some light on this subject matter. Keep in mind I got a 430 a few months ago, so I'm still in the learning process so I am by far not a expert or anything related. But I sure am trying
A. toll, and the equally extravagant marketing push leading up to the Oscars strains
B.toll, and their marketing push is equally extravagant leading up to the Oscars, straining
C.toll, with an even more extravagant marketing push leading up to the Oscars straining
D.toll, while the marketing push leading up to the Oscars is more extravagant to strain
E. toll, while their marketing push leading up to the Oscars is equally extravagant and strains
B & E uses "their" when the subject of the sentence is singular "the film industry" - so they're out.
D is awkwardly worded. Not sure if it's passive tense or something but it's not right.
So it's A and C.
The only reason why I can see that it MIGHT be A is that the "and" is a proper conjunction between the two phrases and is better suited for it than "with" since they are two separate and independent clauses and have no relation between each other. But that's a real real REAL rough guess. And I have no idea about the differences between the "strains" and the "straining" part.