Final answer:
The desirable element of a good system of internal accounting control is that appropriate forms should have preprinted control numbers, ensuring each form is unique for tracking transactions and preventing document tampering.
Step-by-step explanation:
Regarding the question of which element is desirable in a good system of internal accounting control, the answer would be that appropriate forms, such as checks and sales invoices, should have preprinted control numbers. This measure helps to prevent errors and fraud by ensuring that each form is unique and can be accounted for. It aids in the tracking of transactions and the prevention of document tampering. Preprinted control numbers are an important part of an internal control system because they help maintain the integrity of financial records.
By contrast, all accounting personnel in a firm being bonded (option a) might be a good practice but it's not necessary for internal control systems. Option b, the lack of rotation among similar jobs, and option c, the sharing of responsibility and authority among several employees, could actually weaken internal controls by not promoting accountability and transparency. Thus, option d represents a key feature of enforcing accountability and traceability in a company's financial documentation.