Choice "A" is correct. The decision as to whether or not to use analytical procedures as substantive tests is based in part on the availability, reliability, and precision of the data used to develop expectations.
Choice "d" is incorrect. Verification of documentary evidence is a test of details, not an analytical procedure.
Choice "b" is incorrect. The extent of accounting estimates used in preparing the financial statements is not a factor that affects the auditor's decision with respect to the use of analytical procedures as a substantive test. If there is a plausible and predictable relationship, estimated amounts should still fall within expected ranges.
Choice "c" is incorrect. Transaction volume is not a factor that affects the auditor's decision with respect to the use of analytical procedures as a substantive test.