Buddhists believe that nirvana is achieved by following what two things?
the straight and narrow path
the noble eightfold path
the broad way
the high road
the middle way
the low road

the three roles stated in the dialogue develop the siblings' personalities.

lloyd's personality looks like a trademarketer

dana's personality is afraid from lloyd's behavior and the oldest sister is a decided person who tries to solve any conflict

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain