Which word will enable a logical transition between the given sentences?

the lake was always so clear and cool on the hot afternoons at camp. charlotte was an excellent swimmer. she also enjoyed the campfires a lot.

her favorite part was the talent show that campers put on at the end of the summer.

therefore

but

suddenly

thus

#1  sara was always tasked with selecting birthday presents for her friends and family because everyone admired her  impeccable taste. 

impeccable (adj): perfect, flawless

#2  they moved to the united states many years ago, but their  insular  attitudes made it difficult for them to socialize. 

insular (adj): isolated; separate

#3  the professor explained the  semantic  relationship between the two nouns used in the sentence. 

semantic (adj): related to words or the meanings of words 

happy to : )

the answer is b. legendary founder of thebes

could you provide an image?

the answer is c. it calls attention to the urgency of the message