Final answer:
The auditor would add a paragraph after the opinion paragraph in the case where there is serious doubt that the client can continue as a going concern.
Step-by-step explanation:
The correct answer is a. There is serious doubt that the client can continue as a going concern. When there is doubt about a company's ability to continue operating, the auditor adds a paragraph after the opinion paragraph to express their concern. This paragraph is called an emphasis of matter paragraph and is included to alert the reader to the significant issue affecting the company's financial statements.