The correct answer is B because the rapid growth of robo-advisory assets is driven by trends such as increasing demand from 'mass affluent' and younger investors. Traditional investment advice has often overlooked these segments, which typically have lower levels of investable assets.

• A is incorrect because robo-advisers actually face low barriers to entry, as evidenced by large wealth management firms introducing robo-adviser solutions to cater to new investor segments.

• C is incorrect because robo-advisers typically utilize lower-cost investment options like index funds or ETFs when building client portfolios, rather than actively managed funds.