The correct answer is A. Characteristic of or belonging to reality as perceived, rather than as independent of mind
Explanation:
In language, it is common words have multiple meaning but each of them is used in different contexts. This is the case of the word subjective that means related to perception, but can also mean without a substance or use to describe a grammatical element. In the case of "discovering a theme" which refers to determine the underlying idea of a text, the definition or meaning of subjective that applies to this is "characteristic of or belonging to reality as perceived, rather than as independent of mind", because determine or discovering the theme is a process that depends on the perception of reality of individual which means is not objective or independent of mind but depends on each person.
