If a proposition lacks existential import, then:

A) it is false
B) it is true
C) its truth depends only on the relationship of its subject to its predicate
D) its subject class has no referents
E) its predicate class has no referents

A proposition lacking existential import means that it does not assert the existence of the subject. The truth of such a proposition depends only on the relationship between the subject and predicate, regardless of whether the subject or predicate classes have referents or not. For example, the proposition "All unicorns have horns" lacks existential import because unicorns do not exist, but the proposition can still be true based on the relationship between the concept of a unicorn and the concept of having a horn.