Step 1: Understanding the Concept:
The question asks to identify the specific section of the Indian Penal Code (IPC), 1860, that criminalizes acts of promoting hatred, enmity, or ill-will between different groups of people on various grounds, thereby disturbing public tranquility. This is a key provision related to hate speech and public order.
Step 2: Detailed Explanation:
Let's analyze the given sections:
\begin{itemize}
\item S.120A: Defines the offence of criminal conspiracy.
\item S.120B: Provides punishment for criminal conspiracy.
\item S.153A: This section specifically deals with the offence of "Promoting enmity between different groups on grounds of religion, race, place of birth, residence, language, etc., and doing acts prejudicial to maintenance of harmony." The language of the question is a direct reflection of the title and content of this section.
\item S.226: This section has been repealed. It originally dealt with the unlawful return from transportation.
\end{itemize}
Based on the analysis, the offence described in the question is squarely covered by Section 153A of the IPC.
Step 3: Final Answer:
The correct provision for the described offence is S.153A.