In the event a profit-seeking enterprise elects to declare the combined business income tax in accordance with Article 49 of the Financial Holding Company Act and Article 45 of the Business Mergers And Acquisitions Act, the holding company filing the combined income tax return or the parent company after the merger and acquisition shall, in accordance with Articles 9 and 10 of the Act, pay the difference between the ordinary income tax amount and the income basic tax amount prescribed in Paragraph 1, Article 4 of the Act and the increased income tax amount assessed by the competent tax authorities.