The correct answer is C.
OBJ-3.3: This code takes the input of “id” directly from a user or other program without conducting any input validation. This could be exploited and used as an attack vector for an SQL injection. If a malicious user can alter the ID source, it might get replaced with something like’ or ‘1’ =’1. This will cause the SQL statement to become: “SELECT * FROM CUSTOMER WHERE CUST_ID=” or ‘1’=’1′”. Because ‘1’ always equals ‘1’, the where clause will always return ‘true,’ meaning that EVERY record in the database could now become available to the attacker. When creating SQL statements, there are reasons for and against the use of the * operator. Its presence alone does not necessarily indicate a weakness. With only one line of code being reviewed, you cannot make any statement about whether it is vulnerable to a buffer overflow attack. You do not see the declaration values for the initialization of the id variable. This code is not using parameterized queries, but if it did, then it would eliminate this vulnerability. A parameterized query is a type of output encoding that relies on prepared statements to reduce the risk of an SQL injection.