Final answer:
The US state capital closest to 45° N latitude is Pierre, South Dakota, making it the correct answer to the question.
Step-by-step explanation:
The question is asking which US state capital is closest to 45° N latitude. Looking at the options provided: Denver, Colorado; Sacramento, California; Pierre, South Dakota; and Juneau, Alaska, we can determine which capital is nearest to this latitude by checking their respective coordinates.
Upon checking, Pierre, South Dakota is the closest state capital to 45° N latitude, with its coordinates being approximately 44.367966 N, -100.336378 W. Denver, Sacramento, and Juneau are all further from this latitude than Pierre is.
Therefore, the correct answer to the question is C) Pierre, South Dakota.