The term "esoteric" signifies knowledge that is:

The term "esoteric" specifically refers to knowledge that is intended for or likely to be understood by only a small number of people with specialized knowledge or interest. This definition aligns perfectly with the choice indicating that such knowledge is known only by a select few. Esoteric information often pertains to complex subjects that require a certain level of expertise or deep understanding, making it less accessible to the general public. In contrast, the other options suggest knowledge that is broadly accessible or commonly understood, which is contrary to the fundamental meaning of "esoteric."