Database: public_review_platform
Question: User No. 70271 only has given one tip to the Yelp business, which category was that business belonged to?
SQL: SELECT T4.category_name FROM Tips AS T1 INNER JOIN Business AS T2 ON T1.business_id = T2.business_id INNER JOIN Business_Categories AS T3 ON T2.business_id = T3.business_id INNER JOIN Categories AS T4 ON T3.category_id = T4.category_id WHERE T1.user_id = 70271