The correct answer is 2. Semiotics is a study of sign systems because semiotics, as a discipline, focuses on the study of signs, symbols, and their meanings across all forms of communication. Here's how the other options are incorrect or too limited:
Semiotics studies the sound systems of a language:
This describes phonology, not semiotics. Phonology is the branch of linguistics that studies the sound systems in languages.
Semiotics is a study of sign systems (Correct Answer):
Semiotics explores how signs (symbols, words, gestures, images, etc.) convey meaning. It is not restricted to any particular medium or context and can encompass language, media, art, nature, and more.
Semiotics studies human sign system only:
This is incorrect because semiotics applies to both human and non-human systems. For example, animal communication systems can also be studied from a semiotic perspective.
Semiotics is a study of non-human sign systems only:
Semiotics includes human systems as well as non-human ones, so this is too restrictive.
The most accurate and inclusive definition is 2, which captures the full breadth of semiotic study.