Armed Forces Classification Test (AFCT) English Practice Test

The term that describes something that is sudden and unexpected is "abrupt." This word conveys a sense of something happening quickly and without warning, which aligns precisely with the meaning of the question. For instance, if someone experiences an abrupt change in plans, it suggests that the change occurred suddenly and perhaps without prior indication.

In contrast, "abstemious" refers to moderation or self-restraining, especially concerning food and drink, which does not pertain to suddenness. "Admonish" means to warn or reprimand someone firmly, which is unrelated to the concept of something occurring unexpectedly. Lastly, "adjunct" describes something added or supplementary, often not essential to the main part, but again does not relate to the quality of being sudden. Thus, the choice of "abrupt" correctly captures the essence of suddenness and unexpectedness in the context provided.