<|system|>
Is this a sentence fragment?
Closed to visitors since the 1960s, the prehistoric cave paintings in Lascaux, France, are between fifteen thousand and seventeen thousand years old.
A: no
B: yes</s>.
<|user|>
Can you answer based on context?
<|assistant|>
This is not a sentence fragment. It is a complete sentence because it expresses a complete thought.
Closed to visitors since the 1960 s, the prehistoric cave paintings in Lascaux, France, are between fifteen thousand and seventeen thousand years old.