Explanation
A Canadian equity index fund is a type of mutual fund that invests in a portfolio of stocks that track the performance of a Canadian stock market index, such as the S&P/TSX Composite Index. This fund would be the most tax-efficient option for Xerxes, because it has low turnover and generates mostly capital gains, which are taxed at a lower rate than interest income or dividends. A bond fund would generate interest income, which is taxed at the highest marginal rate. An asset allocation fund would have a mix of different types of investments, which may not be optimal for Xerxes' tax situation. A target date fund would adjust its asset mix over time based on a predetermined retirement date, which may not match Xerxes' goals or risk tolerance.
(Canadian Investment Funds Course, Chapter 9, Section 9.2)
References:
Canadian Investment Funds Course, Chapter 9, Section 9.2: Tax-Efficient Investing IFSE Institute: Tax-Efficient Investing1 Investopedia: Tax-Efficient Investing2