Bicycles are banned from Ontario's 400-series highways. Is there anyone at all who may legally ride one on a short stretch of such a highway?

Correct answer: B. Yes — a resident whose land adjoins the highway and has no other road access, by the shortest route

Yes — someone who lives on land beside the highway with no other road access. Regulation 630 s.1(2) exempts "a person who resides on lands adjoining the controlled-access highway to which lands there is no other means of access by highway while such person is engaged in gaining access or egress from such lands, and provided that in gaining such access or egress the person proceeds by the shortest route over such controlled-access highway to the lands." It is a narrow exception with three conditions stacked on it — you must live there, have no other way out, and take the shortest possible route. As a driver the practical point is simply that a cyclist on a controlled-access highway is not necessarily a lawbreaker to be crowded or hooted at; it may be the only way that person can get home.

Source: MTO Driver's Handbook: R.R.O. 1990, Reg. 630 (Vehicles on Controlled-Access Highways), Section 1(2)