Q. Consider the following:
  1. Yardangs are streamlined ridges carved by wind erosion.
  2. Meanders and ox-bow lakes are typical of the mature stages of river development.
  3. Frost wedging occurs because water expands upon freezing in rock cracks.
Which of the above statements is / are correct?

Answer: All of the above
Notes: All three statements are correct: Yardangs indeed result from wind erosion, meanders and ox-bow lakes form in the mature stage of rivers due to lateral erosion and deposition, and frost wedging occurs because water expands when it freezes, breaking apart rock cracks.