An acquisition occurs when:

An acquisition occurs when one company takes control of another company, effectively integrating its operations or assets. This process typically involves the purchasing company acquiring a majority or all of the target company's shares or assets, thereby gaining control over its operations. Acquisitions can be motivated by various factors, including the desire to enter new markets, acquire technology or expertise, achieve synergies, or eliminate competition.

In contrast, the other scenarios listed do not represent acquisitions. For instance, a merger entails the combination of two companies into a single new entity, rather than one overtaking the other. Selling off a division is a process of divestiture, not acquisition, as it involves one company reducing its size or focus rather than expanding through the purchase of another. Rebranding refers to the process of changing the corporate image or identity of a company, which is unrelated to the ownership or control dynamics associated with acquisitions. Thus, option A accurately reflects the defining characteristic of an acquisition.