Method of Reasoning

What we see: Critical Reasoning, method of reasoning. We name HOW the author criticizes the editorial, not whether the author is right.

Step 1. Line up the editorial's two positions.
What we see: on US scientists, the editorial says those with public money cannot "detach themselves from the government's policies on national security." On Soviet scientists, it blames the government for not letting them "detach themselves from politics."
What it means: the same idea, scientists tied to what their government wants, is approved in one country and condemned in the other.
What we do and why: we set the two side by side, because the author's whole point rests on this clash.

Step 2. Read the author's exact move.
What we see: "If there is a significant difference between the principles involved in each case, the editorial should have explained what that difference is."
What it means: the author does not say the editorial is surely wrong. The author says the two positions look like they clash, and that the editorial owes us a reason if they do not.
What we do and why: we look for a choice that describes a clash that only seems to be there. The word "apparent" fits the author's "if there is a difference."

Step 3. Check the choices.
Pointing out an apparent inconsistency: matches both steps. This is the only one that fits.
A. Disputing facts: the author never says any fact in the editorial is false. The author accepts both statements and compares them.
C. An exception to a general claim: an exception would be a new case where the editorial's rule fails. The author brings no new case, only the editorial's own two statements.
D. Refuting an assumption: to refute, the author would have to show that something the editorial takes for granted is false. The author shows nothing false.
E. Different conclusions: the author draws no conclusion of their own from the editorial.

The trap: D. The author does attack the editorial's reasoning, so "refuting an assumption" sounds close. But refuting means proving something false, and the author proves nothing false. The author even allows that a real difference may exist ("If there is a significant difference...") and only asks the editorial to explain it. That is pointing out a clash, not disproving anything.
Faster way: The author quotes the editorial twice, once on each side. When an author puts two of the opponent's own statements next to each other and asks how they fit, the method is pointing out an inconsistency.
Takeaway: In method questions, match the verb to what the author actually did. Quoting both sides of the opponent and asking for the difference is pointing out an inconsistency. Refuting needs proof that something is false.

Answer: B