Among the teenager clients who use Google account and Microsoft account, which group of client is more than the other?
teenager refers to 13 < age < = 19; Google account refers to email like '%@gmail.com'; Microsoft account refers to email like '%@outlook.com'
SELECT CASE WHEN SUM(CASE WHEN email LIKE '%@gmail.com' THEN 1 ELSE 0 END) > SUM(CASE WHEN email LIKE '%@outlook.com' THEN 1 ELSE 0 END) THEN 'Google account' ELSE 'Microsoft account' END FROM client WHERE age BETWEEN 13 AND 19