When the reported ceiling is 1,000 feet overcast and visibility is 3 miles, to remain VFR, an aircraft cleared to the circuit must join
Why this is the answer
Per CAR 602.114, VFR flight in a control zone requires at least 500 ft vertical separation from cloud, so with a 1,000-ft overcast the aircraft must join 500 ft below the cloud base. Joining 'as high as possible' risks entering cloud.
Reference
CARs 602.114 – Minimum Visual Meteorological Conditions for VFR Flight
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.