Rearrange the parts of the sentence to form a coherent statement about the NSG and nuclear trade: The NSG P of nuclear trade, spelt out in its guidelines and trigger lists Q covering every aspect R has already made its rules.

Introduction / Context:
This question tests sentence rearrangement, an important skill in English comprehension. The learner has to arrange three given parts so that the combined sentence is grammatically correct and logically meaningful. The sentence talks about the Nuclear Suppliers Group, often abbreviated as NSG, and how its rules regulate nuclear trade. Understanding how clauses naturally flow in English is crucial to solving such problems.

Given Data / Assumptions:

• Base sentence beginning: The NSG.
• Part P: of nuclear trade, spelt out in its guidelines and trigger lists.
• Part Q: covering every aspect.
• Part R: has already made its rules,
• We must choose the correct order among QRP, QPR, PRQ, and RQP.

Concept / Approach:
In sentence arrangement, the subject and main verb must line up logically. Here, The NSG is the subject. A descriptive phrase about nuclear trade and guidelines must closely follow the subject. The main finite verb has already made should come after the descriptive phrase. Finally, an additional participial phrase can extend the sentence. P begins with of nuclear trade and clearly continues the idea of the NSG. R contains the verb phrase has already made its rules. Q is a participial phrase covering every aspect, which most naturally qualifies the making of rules rather than directly qualifying the NSG. Therefore, a natural English sentence appears when we place P after the subject, then R with the main verb, and then Q as an additional qualifier at the end.

Step-by-Step Solution:
Step 1: Start with the mandatory opening The NSG. Step 2: Attach part P to describe what the NSG relates to. We get The NSG of nuclear trade, spelt out in its guidelines and trigger lists. Step 3: Look for the part that contains the main verb phrase. Part R has has already made its rules, so it should follow next. Step 4: Combine to get The NSG of nuclear trade, spelt out in its guidelines and trigger lists, has already made its rules,. Step 5: Add part Q, covering every aspect, as a participial phrase at the end to modify rules. Step 6: The complete sentence becomes The NSG of nuclear trade, spelt out in its guidelines and trigger lists, has already made its rules, covering every aspect. Step 7: This order corresponds to P first, then R, then Q, which is PRQ.

Verification / Alternative check:
Try the other orders mentally. QRP would begin as The NSG covering every aspect has already made its rules, of nuclear trade, spelt out in its guidelines and trigger lists. This is clumsy and leaves of nuclear trade hanging at the end. QPR would produce The NSG covering every aspect of nuclear trade, spelt out in its guidelines and trigger lists has already made its rules. This is not badly formed, but the phrase covering every aspect more naturally applies to the scope of the rules, which we place at the end in PRQ. Finally, RQP starts with the verb has already made, which cannot directly follow The NSG without the phrase of nuclear trade. Hence, PRQ gives the smoothest standard English sentence.

Why Other Options Are Wrong:
QRP: Makes the sentence awkward and leaves the phrase of nuclear trade in an odd final position.
QPR: Partly works but does not place covering every aspect in the most natural position after the rules.
RQP: Jumps into the verb phrase too quickly and disrupts the normal subject description structure.

Common Pitfalls:
Learners often select an order that sounds acceptable on first reading without checking finer points of clause attachment. A common mistake is to ignore comma placements and relative phrases like spelt out in its guidelines and trigger lists. A good strategy is to first identify the subject, then the main verb, then attach descriptive phrases in a way that avoids dangling or misplaced modifiers. Reading the final sentence aloud in your mind can reveal if it flows naturally.

Final Answer:
The correct order of parts is PRQ, so option c is correct.