How will the right answer fit in terms of support and conclusion?

Only the right answer will be support that guarantees the conclusion.

Highlight the main conclusion in the passage, if there is one:

it is certain that some of the government employees who work in the Hanson Building are computer programmers

[SUPPORT]. Thus [CONCLUSION], since ______.

The author clearly changes the subject when they switch to “work in the Hanson Building”, which is totally different wording from the support about “members of Bargaining Unit Number 17”. The right answer will have to make those two.

Map the wording of the answers to the wording of the passage:

(A) …but are not computer programmers…

This has both of the phrases you’re looking for, but the passage is only about employees who “are computer programmers”. That means this answer is changing the subject, so it doesn’t support the conclusion.

(B) most members of the executive committee..

Stop. The passage doesn’t say anything about who’s on “the executive committee”. That’s bringing in something new, so you’d have to make your own assumption about how the committee connects to “computer programmers”. You’re not allowed to do that, so no way this guarantees the conclusion.

(C) …are members of Bargaining Unit Number 17

They’re trying to get tricky, but this doesn’t actually help the conclusion. That’s because we still don’t know for sure there are computer programmers working in the Hanson Building. It could be only non-programmers who work in the Hanson Building and are members of 17. You know that because the author only said “most” of the members of 17 are programmers.

(D) most of the members of Bargaining Unit Number 17 work in the Hanson Building

Alright, now we know two things about “most members of Bargaining Unit Number 17”: The passage says they’re computer programmers, and this answer says they work in the Hanson Building. So there must be some overlap. Just like you and I can’t both eat most of the pizza, most of the members can’t be programmers and work in Hanson without fighting over the last slice…I mean without overlapping. Who’s ready for lunch?

(E) …are government employees

This isn’t adding any new info, since we know everyone the author mentioned is a “government employee”. So that couldn’t add support, let alone guarantee the conclusion.

(D) is the correct answer.