Uncle Sam--leader of the country or the symbol of the country-- and Lady Liberty-- symbol representing the freedoms and ideals of the country.
The whole country was under investigation and the cartoon suggests all people could be seen as a threat to the country. It also suggests the ideals of the country could even be a threat to the security of the country.
The answer to the question presented above would be letter b. amount of dissolved gases. The increased pressure increases the body's amount of dissolved gases. This change to air pressure greatly affects the human body and these changes can happen when going into the depths of the ocean or when climbing mountain peaks.
TO THE PACIFIC, NOT 100% SURE THO