Which sentence from the passage is the best evidence that ben is eager for the next family road trip to begin?

a.) "under his guidance, the family had traveled last year from their home in michigan across the upper midwest, with a final destination of mount rushmore in south dakota."
b.) "they could camp out while still being at home, and the scenery changed almost every day."
c.) "a new cross-country adventure was just around the corner this summer, and he couldn’t wait to his family plan it."
d.) "ben’s father, an american history teacher, had a thirst for knowledge to rival abraham lincoln’s."