How do Accessible Pedestrian Signals (APS) help a pedestrian with impaired vision know when it's their turn to cross, beyond the usual Walk symbol?

Correct answer: A. Audible and tactile Walk signals, a distinct pushbutton-locating tone, and a tactile directional arrow on the pushbutton itself

APS units add audible and tactile "Walk" indications, plus a separate distinct tone that helps a pedestrian locate the pushbutton itself, and the pushbutton has a tactile arrow aligned with the direction of the crossing along with an acknowledgement tone or vibration confirming it was pressed. As a driver, an APS-equipped crossing is worth extra caution — someone crossing may be relying entirely on sound and touch, not sight, to time their crossing.

Source: MTO Driver's Handbook: Book 12, Section 3.11, Miscellaneous Signals — Accessible Pedestrian Signals