In the context of securitization, the first-loss piece is also referred to as the 'equity piece' or 'equity note'. This term is used because this piece is the most junior tranche in the securitization structure and is the first to absorb losses, similar to how equity shareholders are the first to bear losses in a company. This piece is usually held by the originator of the securitization process, as it carries the highest risk and potential for returns. The equity piece is the last to receive payments but has the highest yield due to its risk profile. It is important to note that despite being called an 'equity piece', it is actually a bond.

Choice B is incorrect. The term "At-risk note" is not used in the context of securitization to refer to the first-loss piece. This term does not specifically denote the highest risk level associated with a securitized asset pool.

Choice C is incorrect. The term "First-risk note" is also not used in this context. While it may seem similar, it does not accurately represent the concept of a first-loss piece in securitization, which bears the highest risk and potential for losses.

Choice D is incorrect. Although "Junior piece" can be associated with higher risk levels in some contexts, it does not specifically refer to the first-loss piece in securitization process. In fact, junior pieces often have lower priority compared to senior pieces but they are not necessarily designed to absorb initial losses.