你需要展示所有cust_first_name列里有'e'而且倒数第二位为'a'的用户的所有信息。 哪个查询将提供所需的输出？A A SELECT * FROM customers WHERE INSTR(cust_first_name, 'e')<>0 AND SUBSTR(cust_first_name, -2, 1)='a'; B SELECT * FROM customers WHERE INSTR(cust_first_name, 'e')IS NOT NULL AND SUBSTR(cust_first_name, 1,-2)='a'; C SELECT * FROM customers WHERE INSTR(cust_first_name, 'e')<>'' AND SUBSTR(cust_first_name, -2, 1)='a'; D SELECT * FROM customers WHERE INSTR(cust_first_name, 'e')<>0 AND SUBSTR(cust_first_name, LENGTH(cust_first_name),-2)='a';