Crossing a divided highway with a wide median, you stop at a STOP sign for the first roadway, cross, and then find a YIELD sign facing you in the median before the second roadway. Is that a mistake?

Correct answer: B. No — a wide median makes it two crossings, so the second roadway gets its own control; check again for traffic from the other direction

No — it is a deliberate pairing. Book 5 lists a YIELD sign as appropriate "within an intersection of a road with a divided highway" where "there is a STOP sign approaching the intersection with the roadway upstream of the median", where "further control is necessary at the approach to the intersection of the roadway downstream of the median", and "where the median width exceeds 10 m." A median that wide is effectively two separate crossings, and the traffic on the far roadway is coming from the other direction — nothing you checked at the first stop line tells you about it. So the second half gets its own control, and a yield rather than a second stop because you are already moving slowly. Treat it as a fresh decision: look the other way, and stop if you need to.

Source: MTO Driver's Handbook: Ontario Traffic Manual, Book 5 — Regulatory Signs (December 2021), Section 3 — YIELD RIGHT-OF-WAY Signs, Guidelines for Use, divided highway application