An arriving VFR flight shall make initial radio contact with the control tower
Why this is the answer
Initial contact with the control tower must be made prior to entering the Control Zone, not after, so clearance/communication is established before you cross the boundary (TC AIM-RAC; CARs 601.08). The TC AIM recommends calling about 5 minutes out.
Reference
CARs 601.08 – VFR Flight in Class C Airspace TC AIM-RAC – Arrival Procedure – Controlled Airports, Initial Contact
Question reproduced verbatim from Transport Canada’s PSTAR Study and Reference Guide (TP 11919E). The answer key is Transport Canada’s; the explanation is ours.
A study aid — not a substitute for the official guide, the CARs, or your instructor.