The 18-year-old, who scored and was voted Man of the Match in Sunday's 2-2 draw with Liverpool, was taking part in our Fans' Q&A series, in association with Melitta.
Kobbie opted for Paul Scholes, a man who won 11 Premier League titles with his boyhood club, and number three on the all-time appearances list.
Scholesy, who turns 50 in November, came out of retirement to extend his career and helped Sir Alex Ferguson's team win the league in 2012/13.
Mainoo, who has been at United since a schoolboy, was only eight when the Reds wrapped up the final championship of Ferguson and Scholes's time at the club, and has always respected the ability and sheer quality of somebody who plays in the same position as him.