Which of the following pairs are are desert landforms?

The desert landforms among the given pairs are yardangs and zeugens. Yardangs are long, narrow ridges with steep sides that are carved out of the bedrock by wind erosion. They are formed by the deflation of loose sand and silt, leaving behind harder, more resistant rock formations. Zeugens, on the other hand, are elongated ridges or hills that are formed by the wind erosion of a softer rock layer, leaving behind a more resistant layer on top. They are often found in desert landscapes where there are alternating layers of hard and soft rock. Wave-cut platforms are features formed by the erosion of coastal cliffs by waves, while self-dunes are small, isolated sand dunes that form on a flat surface, often around a single rock or obstacle. Sandbars and sandspits are coastal landforms formed by the deposition of sand by waves and currents, while barchans and tombolos are sand dunes and ridges that form in desert and coastal environments, respectively. Therefore, the correct answer is yardangs and zeugens.