Executing the Commit tran statement

I found an example like this:
TransactionOptions options = new TransactionOptions();
options.IsolationLevel = System.Transactions.IsolationLevel.ReadCommitted;
options.Timeout = new TimeSpan(0, 2, 0);
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.Required, options))
{
using (SqlConnection connA = new SqlConnection(connStringA))
{
using (SqlCommand cmdA = new SqlCommand(sqlStmtA, connA))
{
int rowsAffectedA = cmdA.ExecuteNonQuery();
if (rowsAffectedA > 0)
{
using (SqlConnection connB = new SqlConnection(connStringB))
{
using (SqlCommand cmdB = new SqlCommand(sqlStmtB, connB))
{
int rowsAffectedB = cmdB.ExecuteNonQuery();
if (rowsAffectedB > 0)
{
transactionScope.Complete();
}
} // Dispose the second command object.
} // Dispose (close) the second connection.
}
} // Dispose the first command object.
} // Dispose (close) the first connection.
} // Dispose TransactionScope object, to commit or rollback transaction.

My question is: do I have to use the If(rowsAffectedA > 0) to go for the next transaction, or I can directly go for transactions 1,2,3,4 and If one fails, at the end - the scope object will automatically roll back all? If it does, should I call the Complete() method anyway?

Thanks.