Two polygons are similar when the length of their sides is proportional and their internal angles are the same. To check which polygons are similar we need to check the sides, all the sides of the polygon must increase or decrease by the same factor.
With this in mind let's check each polygon.
The polygon EFGH had its length increased, but the height remained the same, therefore it can't be similar to ABCD.
The polygon IJKL got its height decreased in a factor of 2, while the length also decreased by a factor of 2. Therefore it is similar to ABCD.
The polygon MNOP got its height increased by a factor of 1.5, while the length also got increased by the same factor. Therefore it is similar to MNOP.
The polygons that are similar to ABCD are: IJKL and MNOP.