The labelled sentences X, Y and Z are: X - first appear, is quite in accordance, as; Y - before stated, with the analogy of changes; Z - now going on in certain regions of the globe. Which order forms the most logical continuation of "This idea, however startling it may at..."?

Introduction / Context:
This question presents a partially broken sentence that must be reconstructed using three labelled segments X, Y, and Z. The sentence begins with This idea, however startling it may at and must be completed to form a grammatically correct and logically ordered statement. The sentence discusses an idea that first seems surprising but is actually consistent with other changes occurring in certain regions of the globe.

Given Data / Assumptions:

• The fixed beginning is: This idea, however startling it may at ...
• X: first appear, is quite in accordance, as
• Y: before stated, with the analogy of changes
• Z: now going on in certain regions of the globe
• The final sentence should read smoothly both grammatically and in terms of meaning.

Concept / Approach:
We need to reconstruct a complex sentence that uses the phrase however startling it may at first appear and then connects this idea to earlier statements and to actual changes taking place in certain regions of the globe. The natural order is to complete the phrase may at first appear (X), then refer back to what was before stated (Y), and finally describe the location of the changes (Z). This yields: This idea, however startling it may at first appear, is quite in accordance, as before stated, with the analogy of changes now going on in certain regions of the globe. This sequence corresponds to X Y Z, giving option B.

Step-by-Step Solution:
Step 1: Join the beginning with X: This idea, however startling it may at first appear, is quite in accordance, as...Step 2: Recognise that as must refer to something previously mentioned, namely before stated, with the analogy of changes (Y).Step 3: Append Y to X: ...is quite in accordance, as before stated, with the analogy of changes...Step 4: Add Z to complete the reference: ...with the analogy of changes now going on in certain regions of the globe.Step 5: Confirm that the resulting sentence is grammatical and carries a clear logical progression from apparent surprise to consistency with observed changes.

Verification / Alternative check:
Test other orders. If we start with Z, we would get may at now going on in certain regions of the globe, which is clearly ungrammatical. Starting with Y would give may at before stated, with the analogy, which does not complete the phrase may at and breaks the idiom at first appear. Thus, X must come immediately after may at. Once X is fixed, the rest of the sentence should lead from as to before stated (Y) and then to the explanation of where the changes are occurring (Z). The only order that achieves this is XYZ.

Why Other Options Are Wrong:
Option A ZYX begins with now going on in certain regions of the globe directly after may at, which produces a broken phrase and no clear meaning. Option C ZXY and option D YZX both disturb the essential idiom at first appear and the proper referencing sequence as before stated. None of these alternative sequences yields a smooth, logically connected sentence when read in full.

Common Pitfalls:
Students sometimes focus only on the content words like changes and globe and attempt to place those fragments first, forgetting the importance of fixed phrases such as at first appear. A reliable strategy in jumbled sentence questions is to identify such idiomatic pairs and keep them together: here, at must be followed by first appear from X. Next, pronouns or linking phrases such as as before stated usually refer to earlier material and therefore appear after the main clause, not immediately after may at.

Final Answer:
The most logical order of the segments is XYZ, so option B is correct.