Which of the following is the largest hawk?

The term "jerkin" refers to a male hawk that is typically larger in size compared to the other options listed. In falconry terminology, a "jerkin" often denotes a male of medium- to large-sized hawk species, and sometimes it can refer to specific types of hawks that exhibit noticeable size differences. This term is particularly relevant when comparing birds of prey within the context of size classifications in the sport of falconry.

On the other hand, the other choices represent various designations or terms related to birds of prey, but not specifically referring to sizes as distinctly as "jerkin." The term "tiercel" refers to a male falcon, which is usually smaller compared to a female of the same species. "Jack" can refer to smaller male hawks or specific juveniles but generally pertains to smaller sizes. The term "falcon" encompasses a broader category of birds that includes various species, typically less about size and more about classification.

Therefore, in understanding the context of size among these terms, the designation of a "jerkin" fittingly identifies the largest hawk option in this context.