Actually, none of those choices are correct. You get back 50 random GUID values.
1. NEWID() returns a random GUID (aka uniqueidentifier)
2. Select statement has no order by clause, so the results are random.
3. The GO 50 repeats that batch 50 times (if in SSMS and the batch separator is set to "GO")
The answer annotated as correct ("50") is not correct... the results are 50 random GUID values. You do NOT receive "50" as the result set to this query.
I ended up reading the question, reading the answers, deciding that I must be losing my mind, running the query to see what I was missing, re-reading the answers, and deciding that I had no idea how to translate the actual results into the list of possible answers.
So I'm not answering today's question unless we end up with a set of answers that actually matches the question.