Air pollution is likely to be most severe

The correct answer is: A. in the interior of continents.

Air pollution is likely to be most severe in the interior of continents because of the following reasons:

• The interior of continents is far from the oceans, which are a major source of clean air.
• The interior of continents is often located in areas with dry climates, which can lead to dust storms and other forms of air pollution.
• The interior of continents is often home to large cities, which generate a lot of air pollution.

Option B, near the center of an anticyclone, is incorrect because anticyclones are areas of high pressure, which tend to trap pollutants near the ground.

Option C, in the summer, is incorrect because air pollution is often worse in the winter due to the use of heating systems.

Option D, when the atmosphere is turbulent, is incorrect because turbulence can help to mix pollutants with the atmosphere and disperse them.