Explanation
Box 1:

Box 2:

Box 3:

Box 4: transaction.Commit();
Box 5:

Box 6: transaction.Rollback();
Box 7: } finally {
Box 8:

Note:
* Box 1: Start with the sqlconnection
* Box 2: Open the SQL transaction (RepeatableRead)
/ IsolationLevel
Specifies the isolation level of a transaction.
/ RepeatableRead
Volatile data can be read but not modified during the transaction. New data can be added during the transaction.
/ ReadCommitted
Volatile data cannot be read during the transaction, but can be modified.
/ ReadUncommitted
Volatile data can be read and modified during the transaction.
Box 3: Try the query
Box 4: commit the transaction
Box 5: Catch the exception (a failed transaction)
Box 6: Rollback the transaction
Box 7: Final cleanup
Box 8: Clean up (close command and connection).
Reference: SqlConnection.BeginTransaction Method
Incorrect:
The transaction is not set up by transactionscope here. Begintransaction is used.