Final answer:
Growing too large is not a reason for poor long-term performance resulting from an acquisition.
Step-by-step explanation:
The option that is NOT a reason for poor long-term performance resulting from an acquisition is b. growing too large. When a company grows through acquisition, it typically aims to achieve synergy, diversification, and growth opportunities. However, growing too large is not a reason for poor performance; in fact, it can be a desired outcome of a successful acquisition.