Which of the following are PCAOB Attestation General Standards? Multiple select question. The report shall state all of the practitioner's significant reservations about the engagement. Sufficient evidence shall be obtained to provide a reasonable basis for the opinion expressed in the report. The engagement shall be performed by a practitioner having adequate knowledge of the subject matter. The work shall be adequately planned and assistants, if any, should be properly supervised. Due professional care shall be exercised in the planning and performance of the engagement.