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20. Select the image you want to add instead of the question mark.
  IQ test. Fast and free online iq test # 4 with answers and solutions. Question # 20. Select the image you want to add instead of the question mark.
 

Explanation:
If you analyze the change of figures in each line from the left to the right, you can determine that: the figure in the upper line is stretched vertically; the figure in the middle line is stretched horizontally; the figure in the bottom line is stretched from inside out.