Which storage group is the default storage group for the TESTDB database?

If the following SQL statements are executed:

CREATE DATABASE testdb AUTOMATIC STORAGE NO;

CONNECT TO testdb;

CREATE STOGROUP sg1 ON ‘/data1’;

CREATE STOGROUP ibmstogroup ON ‘/data2’;

CREATE STOGROUP sg2 ON ‘/data3’;

Which storage group is the default storage group for the TESTDB database?
A . SG1
B . SG2
C . IBMSTOGROUP
D . IBMDEFAULTTSG