Which of the following is especially vulnerable to misinterpretation in online environments, given the ambiguity that is inherent to text-based communications (e. g., texting, instant messaging, aggression o frustration o trolling o sarcasm

Sarcasm.

Sarcasm expressions are heavily dependant on the context, voice tone, and even facial expressions to be correctly understood. Therefore, it's widely used in spoken language.

When in an online environment, it's not possible to display a voice tone or facial expressions that help the receiver to understand that what you are saying, is not literal, and thus, it can be misunderstood

answer; in small towns;