题目选项分析

Advertisement: Last year, Factorial Mutual Fund continued its strong record of investment performance. Investors who included Factorial Fund in their portfolios realized an average capital gain of 15% across all of their investment assets, nearly double the market return. Therefore, investors interested in high returns should consider adding Factorial Mutual Fund to their portfolios.

The claim in the advertisement above is based on which of the following assumptions?

【选项】The fees charged by Factorial Fund are among the lowest in the investment industry.