Which geographic feature presented an obstacle to simon bolivars forces

The Andes mountain was the geographical feature that presented an obstacle to Simon Bolivars forces. Simon Bolivar was born on 24th July 1783 and he died on 17th December in the year 1830. He was born in a very wealthy and an aristocrat family. He was a not only a person belonging to the military of Venezuela, but he was also a political leader who played a big role in getting independence from the Spanish rule. At a tender age of 14, Bolivar saw his private instructor running away from the country on charges of treachery. This led him to join the military academy to learn the arts of fighting.

The answer is option a. boundary line drawn by pope alexander iv in 1493.