Final answer:
The statement that TOSI may apply to amounts received by adult family members is true. TOSI aims to prevent income splitting to reduce taxes by shifting income to those in lower tax brackets. It applies to specific types of income paid to family members by businesses.
Step-by-step explanation:
The statement regarding the Tax on Split Income (TOSI) is true. TOSI can indeed apply to amounts received by adult family members who are age 18 and older. The purpose of TOSI is to prevent income splitting amongst family members in a way that reduces the overall tax burden by shifting income to those in lower tax brackets. The tax is designed to apply to certain types of income, such as dividends and business income, that are paid to family members by a business where they may not be actively involved to a sufficient extent. Therefore, adult family members receiving such income could be subject to TOSI if specific criteria are met.