Which factors can influence the form of a dialect?

The correct answer identifies geographical region and social class as significant factors that influence the form of a dialect. A dialect is shaped by the environment in which it develops, including the specific geographical area where speakers reside. Different regions often have unique linguistic features, such as vocabulary, pronunciation, and grammar.

Social class also plays a critical role in dialect formation. Variations in dialect can signal social identity, indicating a speaker's socioeconomic background. Different social classes may adopt distinct speech patterns, leading to noticeable differences even within the same geographical region.

Other options, although relevant in language studies, do not pertain directly to the factors that shape dialect. Literary techniques and narrative structure focus more on written texts and storytelling rather than spoken language. Rhetorical devices and critical theory are related to the analysis of language and its persuasive use, rather than the formation of dialects. Meanwhile, grammar rules and spelling conventions pertain more to standardized written language than to the variations found in spoken dialects.