Concept:"Trivial" means of little value or importance, small and not worth serious attention.
Solution:"Lance only talks about trivial matters" means he talks only about small, unimportant things.
So the nearest meaning is "unimportant".
B. "unpleasant" means not nice or not enjoyable.
C. "unacceptable" means not allowed or not good enough.
D. "unexciting" means dull; trivial matters may be dull, but the word itself is about importance, not excitement.
Key point: All four options start with "un-"; look at the root word: important, pleasant, acceptable, exciting.
Answer:Option A (unimportant)