An ATC clearance means an authorization by ATC, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified conditions within controlled airspace. It is not autorization for a pilot to deviate from any rule, regulation, or minimum altitude nor to conduct unsafe operation unsage operation of the aircraft. The pilot-in-command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft. If ATC issues a clearance that would cause a pilot to deviate from a rule or regulation, or in the pilot's opinion, would place the aircraft in jeopardy. It is the pilots responsibility to request an amended clearance.
Is this last sentence a Brazilian rule, or is it in accord with ICAO? If a pilot is not aware (and cannot be aware, unless informed by ATC) of a specific hazard, is he thus culpable?