Qualified, Adverse, Disclaimer — when and how to modify.
To express clearly a modified opinion when the auditor concludes that the FS are not free from material misstatement, or is unable to obtain sufficient appropriate audit evidence.
SA 705 sits in the Reporting phase of the audit. The Standards on Auditing are issued by the ICAI Auditing and Assurance Standards Board (AASB) and deemed to be prescribed by the Central Government under Section 143(10) of the Companies Act 2013. Compliance with SAs is mandatory for every audit conducted by a Chartered Accountant in India.
For authoritative text, refer to the ICAI AASB Compendium of Standards on Auditing at icai.org.