Answer: INTERSECT

The INTERSECT operator is specifically designed to return only the rows that appear in both result sets, which directly matches the requirement of finding values present in both tables. The community discussion confirms this with 100% consensus on answer A, and the referenced Snowflake documentation explicitly states that INTERSECT 'returns rows from one query's result set which also appear in another query's result set.' Other options are less suitable: MERGE is for upsert operations, MINUS returns rows in the first set but not the second, and UNION combines all rows from both sets (including duplicates unless UNION ALL is specified).

Author: LeetQuiz Editorial Team