Authorize.net : How can I do whether the credit card is valid or invalid?

How can I do whether the credit card is valid or invalid?
I got the result:
:(:(:(

0 Response Code 1  
1 Response Subcode 1  
2 Response Reason Code 1  
3 Response Reason Text (TESTMODE) This transaction has been approved.  
4 Approval Code 000000  
5 AVS Result Code P  
6 Transaction ID 0  
7 Invoice Number   
8 Description   
9 Amount 10.00  
10 Method cc  
11 Transaction Type auth_capture  
12 Customer ID   
13 Cardholder First Name xxxxxx
14 Cardholder Last Name xxxxxx
15 Company   
16 Billing Address xxxxxx
17 City xxxxxx
18 State xx
19 Zip xxxxxx
20 Country US  
21 Phone xxxxxxxxx
22 Fax   
23 Email [email protected]  
24 Ship to First Name   
25 Ship to Last Name   
26 Ship to Company   
27 Ship to Address   
28 Ship to City   
29 Ship to State   
30 Ship to Zip   
31 Ship to Country   
32 Tax Amount   
33 Duty Amount   
34 Freight Amount   
35 Tax Exempt Flag   
36 PO Number   
37 MD5 Hash AEBCFED5EAB80D363DF8D5588B4245BE  
38 Card Code (CVV2/CVC2/CID) Response Code   
39 Cardholder Authentication Verification Value (CAVV) Response Code   
40 Reserved Field 0   
41 Reserved Field 1   
42 Reserved Field 2   
43 Reserved Field 3   
44 Reserved Field 4   
45 Reserved Field 5   
46 Reserved Field 6   
47 Reserved Field 7   
48 Reserved Field 8   
49 Reserved Field 9   
50 Reserved Field 10   
51 Reserved Field 11   
52 Reserved Field 12   
53 Reserved Field 13   
54 Reserved Field 14   
55 Reserved Field 15   
56 Reserved Field 16   
57 Reserved Field 17   
58 Reserved Field 18   
59 Reserved Field 19   
60 Reserved Field 20   
61 Reserved Field 21   
62 Reserved Field 22   
63 Reserved Field 23   
64 Reserved Field 24   
65 Reserved Field 25   
66 Reserved Field 26   
67 Reserved Field 27   
68 Merchant Defined Field 0 FALSE  

kJohns:

0 Response Code 1
1 Response Subcode 1
2 Response Reason Code 1
3 Response Reason Text COLOR="Red" This transaction has been approved. [/COLOR]

When I changed my security number(CVV) to other number

$a->add_field('x_card_code', '111');

to

$a->add_field('x_card_code', '222');

It still ok

So, how can I validate credit card with security number(CVV code)?
How can I fix it?