Which of these was key to the American victory at the Battle of Saratoga in 1777?

Question

Responses
A defensive positions along a ridge linedefensive positions along a ridge line
B coastal fortifications along New York Harborcoastal fortifications along New York Harbor
C severe flooding forced the British to retreatsevere flooding forced the British to retreat
D the ability to cut off traffic on the Mohawk River

Answer 1

A defensive positions along a ridge line