which

[confuse mind]

If an SC question contains:

X and Y, which ...

then which modifies Y or 'X and Y'

Similarly,

X or Y, which ...

then which modifies Y or 'X or Y'

[Jim@StratusPrep]

which defines Y for both of these examples.

[EducationAisle]

Yeah, it looks like GMAT prefers to use "that" when a "list" needs to be modified. Following is a correct sentence form OG Verbal:

The computer company's present troubles are a result of technological stagnation, marketing missteps, and managerial blunders that several attempts to revise corporate strategies have failed to correct.

[confuse mind]

which defines Y for both of these examples.

Thanks Jim.
And I hope the same is true for other relative pronouns, such as, who, that, etc. and corresponding essential and non-essential modifiers. No?

Ram and Shyam who...........
Ram or Shyam who.............

Ram and Shyam, who......, .....
Ram or Shyam, who......., ......

Books and notebooks that ......
Books or notebooks that .......


What would be the correct sentence if want to modify both X and Y in such sentences:

X and Y
X or Y