Y has been believed to cause Z. A new report, noting that Y and Z are

Question

Y has been believed to cause Z. A new report, noting that Y and Z are often observed to be preceded by X, suggests that X, not Y, may be the cause of Z.

Which of the following further observations would best support the new report’s suggestion?

(A) In cases where X occurs but Y does not, X is usually followed by Z.
(B) In cases where X occurs, followed by Y, Y is usually followed by Z.
(C) In cases where Y occurs but X does not, Y is usually followed by Z.
(D) In cases where Y occurs but Z does not, Y is usually preceded by X.
(E) In cases where Z occurs, it is usually preceded by X and Y.

KarishmaB · Accepted Answer

Old Belief: Y --> Z

New Observation: X --> Y, Z

New Suggestion:
X --> Z
Y -/-> Z

We need the observation that strengthens that X, not Y, causes Z.

(A) In cases where X occurs but Y does not, X is usually followed by Z.
Perfect. When X occurs, but Y does not, often Z occurs. So it does seem to show that X, not Y, causes Z.

(B) In cases where X occurs, followed by Y, Y is usually followed by Z.
This could mean that X causes Y and then Y causes Z. But we are to conclude that X, NOT Y, causes Z. So wrong.

(C) In cases where Y occurs but X does not, Y is usually followed by Z.
This shows that Y --> Z. Wrong

(D) In cases where Y occurs but Z does not, Y is usually preceded by X.
It seems X does not cause Z in this case.

(E) In cases where Z occurs, it is usually preceded by X and Y.
Here either X or Y could cause Z. No conclusion.

Answer (A)

naval2272 · Answer

Any scenario in which x in the absence of y results into z, will strengthen the argument.

A) correct

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Skywalker18 · Answer

Y has been believed to cause Z. A new report, noting that Y and Z are often observed to be preceded by X, suggests that X, not Y, may be the cause of Z.

Which of the following further observations would best support the new report’s suggestion?
Boil it down - X may be the cause of Z (Y might be just a correlation) and X precedes Y and Z.

(A) In cases where X occurs but Y does not, X is usually followed by Z. - Y is absent and the order is what was need - Correct

(B) In cases where X occurs, followed by Y, Y is usually followed by Z. - Incorrect - we can conclusively say Y DOES NOT cause Z here

(C) In cases where Y occurs but X does not, Y is usually followed by Z. - Opposite -- so Z can occur even in the absence of X and Y-->Z

(D) In cases where Y occurs but Z does not, Y is usually preceded by X. - Irrelevant

(E) In cases where Z occurs, it is usually preceded by X and Y. - Incorrect - does not help to zero in on the causality

Answer A

VerbalBot · Answer

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Y has been believed to cause Z. A new report, noting that Y and Z are

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