I think there's slight difference among the answers 3,4,5 as "state" sometimes means "nation" or "local government beloning to state".
If you have any other different opinion, please let me know. Is there any strict distinction between "of state" and "of the nation"?
. In the diagluge below, which is same as (B)state?
① The witness stated that he had seen the man enter the building.
② The press attaches no small importance to the present state of the country. ③ How many state universities are there in L.A.? ④ She was selected to represent the state of Texas at the conference. ⑤ The half-priced apartments are constructed on state-owned land.

Byeongman'd Dad: Here we are. We are going to stay the night here.
Byeongman: Lake Char ... What kind of name is this? I can't (A)even read it.
Byeongman'd Dad: Well, it's a Native American name. You know, North America, originally, was the land of the Native Americans.
Byeongman: You mean Europeans simply took the Native American place names?
Byeongman'd Dad: Right. About half of the (B)state names in the U.S. are from Native American words.
Byeongman: That's a lot.
Byeongman'd Dad: Yes, and many rivers, mountains and waterfalls also have Native American names.
Byeongman: I see. But this lake... The name is too long.
Byeongman's Dad: Don't worry. People just call it Webster lake.
Byeongman: By the way, is it all right if I swim in the lake? The water looks so clean.
Byeongman'd Dad: Sure. But make sure you don't go too far. The lake could be deep in the center.
Byeongman: Don't worry, I won't.