In which of these options will the parents avoid paying taxes on investment income earned towards their child's education?

When parents invest the Canada Child Tax Benefit in the name of the child, they effectively utilize the child's tax situation to minimize or avoid taxes on investment income. This is because children typically have lower income levels and can benefit from a basic personal tax credit, which allows for tax-free earnings up to a certain amount.

Investment income earned in the child's name can remain within the child's tax threshold, ensuring that it is subjected to lower taxes than if it were in the parent’s name. The tax implications are significant because, depending on the amount of investment income, it may not be taxed at all if it stays within the child's non-taxable income limit.

On the other hand, the other options may not offer the same tax efficiency. For instance, investments in a high-interest savings account, direct stock purchases, or a regular savings account could still generate taxable income that might create tax liabilities for the parents or the child depending on ownership and tax brackets. Thus, the approach of investing the Canada Child Tax Benefit directly in the child's name is a strategic way to ensure tax avoidance on those funds meant for education.