The correct answer is: A. ED
The member ED does not carry zero force in the structure shown in the figure.
The member ED is a diagonal member in a truss. Diagonal members in a truss are always in tension. This is because the diagonal members are used to transfer the load from the top chords to the bottom chords. The load from the top chords is transferred to the diagonal members, which then transfer the load to the bottom chords. The diagonal members are always in tension because they are trying to pull the top chords and the bottom chords together.
The other members in the structure are all in compression. This is because the load from the top chords is transferred to the bottom chords through the vertical members. The vertical members are in compression because they are trying to push the top chords and the bottom chords together.
The member ED is the only member in the structure that is not in compression. This is because the member ED is not transferring the load from the top chords to the bottom chords. The member ED is only transferring the load from the top chords to the diagonal members.
The member ED is in tension because it is trying to pull the top chords and the diagonal members together. The member ED is the only member in the structure that is not in compression.