During the vietnam war, us troops had the advantage of
college deferments.
access to chinese military resources.
superior geographic knowledge of the region.
superior firepower.

During Vietnam War, US troops had the advantage of superior firepower. The correct option among all the options that are given in the question is the fourth or the last option. The United States forces did have a superior firepower but they lacked geographic knowledge of the region. This was one reason that the Vietnam forces never let the US forces have a complete victory. 

So the answer to this question would have to be D!! :))

Asuffragette was a member of militant women's organisations in the early 20th century who, under the banner "votes for women", fought for the right to vote in public elections, known as women's suffrage.