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8. Select the image you want to add instead of the question mark.
  IQ test. Fast and free online iq test # 1 with answers and solutions. Question # 8. Select the image you want to add instead of the question mark.
 

Explanation:
Each line and each column contain: one picture with horizontal semicircles and two pictures with vertical semicircles; horizontal semicircles on one picture are painted in the same color (either black or white); pictures with vertical semicircles differ in inversed manner.