Step 1: Understanding the Concept:
The question asks for the statutory minimum notice period required to call a general meeting of a company. This is a crucial procedural requirement to ensure that members have sufficient time to prepare for the meeting. The question specifically refers to Section 171 of the Companies Act, which is from the 1956 Act.
Step 2: Detailed Explanation:
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\item Under the Companies Act, 1956: Section 171(1) explicitly stated that a general meeting of a company may be called by giving not less than twenty-one days' notice in writing.
\item Under the Companies Act, 2013: This provision has been retained in Section 101(1). It states that a general meeting may be called by giving not less than clear twenty-one days' notice either in writing or through electronic mode. The term "clear days" means that the day of sending the notice and the day of the meeting are both excluded from the calculation.
\end{itemize}
Both the old and new Acts prescribe a 21-day notice period. Therefore, the correct answer is 21 days.
Step 3: Final Answer:
A general meeting may be called by giving a notice in writing for not less than 21 days.