The answer is c
bt opening the window ...
B - John Muir, the famous naturalist and champion for National Parks shared this wisdom about the calming effects of the natural world: ___
A colon is used between two independnt clauses. In this case the second clause explains the first - it is his actual quote and 'wisdom' that he is sharing.
The answer is b., due to how the rhythm seems to be more fluidic
