Which term refers to someone who is quietly reserved or not inclined to speak?

The term that accurately describes someone who is quietly reserved or not inclined to speak is "reticent." This word specifically refers to a person who tends to be reserved in their communication, often not revealing their thoughts or feelings readily. It implies a sense of shyness or reluctance to provide information, which aligns perfectly with the description given.

In contrast, "inquisitive" refers to someone who is curious and eager for knowledge, often asking questions and seeking information. "Dogmatic" describes someone who is strongly opinionated and asserts their beliefs in a rigid manner, showing little room for other viewpoints. "Morose," on the other hand, indicates a gloomy or sullen disposition and does not focus on the reserved nature of communication but rather on a temperament that may be silent due to sadness or melancholy. Thus, "reticent" is the most fitting choice in this context.