A merger is when two companies join into one, and an acquisition is when one company buys and takes control of another. Companies do this for a business reason, not just to feel important. Let's look at what each option means.
Since a merger or acquisition is mainly a tool to grow the business quickly, gain market share, and add new strengths, the correct option is "expansion and growth".
Let's summarize:
So the answer is option (1), expansion and growth.