Which feature of civilization describes a shared set of Spiritual beliefs

The correct answer is D) The American flag occupies much of the space.

You forgot to include the painting. However, doing some research we can say the following.

What suggests that the artist of the painting is most likely an American is that the American flag occupies much of the space.

If we observe the painting, we can see a man that is unfurling the American flag that is at the very top of the flagpole. A group of soldiers on one side and a group of civilians on the other are witnessing the event. We can see that the American flag has a prominent place in the painting.