Answer:
1. The gingko is a curious tree
Step-by-step explanation:
The sentence that states an opinion is:
"(1) The gingko is a curious tree."
This sentence contains the word "curious", which is a subjective term that expresses an opinion rather than a fact. While it is true that the ginkgo is a distinct tree species, describing it as "curious" is a matter of personal interpretation and therefore an opinion.