The first picture is taken by Sebastião Salgado. This is a black & white photo taken at Antarctica, showing a line of penguins on an iceberg. This photo’s foreground and background are all razor sharp – you can see the texture of the ice in the front, while also be able to clearly see the rough texture of the cliff at the back. This is an example of deep (long) depth of field. The deep depth of field in combination with the wide field of view gives the viewer a spectacle of the wild, deserted and dangerous Antartica, showing the braveness of the penguins.
The second picture, Veteran with a flag, is shot by Diane Arbus. This is also a black & white photograph. However, unlike the previous work by Salgado, this picture’s foreground is sharp, while the background is soft and blurry. This is an example of shallow (short) depth of field. This not only draws viewers attention directly to the subject itself, but also isolate the subject from the noisy background. While the background is blurred, the aperture didn’t seem to be overly large, letting viewers still be able to vaguely see the protest going behind this man’s back. This way, we can still tell the larger context of the picture, but the major focus is the veteran himself.
Your choices and descriptions show that you understand depth of field, deep and shallow.