ASA 2014 test question 16

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Question 16 of the ASA 2014 test:
With two outs and R1 on 3B, B4 get a base hit. R1 should score easily but is knocked down by F5. B4 tries to stretch a single into a double and is tagged out before reaching 2B for the 3rd out. Does the run count?

I’m think’n there isn’t enough information. Was obstruction called and DDB signaled? Did runner get up and go home? Did runner stay on ground?
If there isn’t information missing I’m think’n this is a great question. I can’t find anything on this but that’s me.

My ruling if I had to use the knowledge instantly on the field, and my logic cuz I can’t find anything: Run scores cuz defense can’t benefit by knocking down a runner and getting an out somewhere else, no matter the timing, to prevent the run from scoring. It would have been, my judgment, the run scored before the out was made at second.....or, after play is over tell'm rrun would have scored had they not been obstructed and it would have scored before the out at 2nd.
Am I completely wrong here? If my logic’s wrong, where?
Thanks………..