Final answer:
Sedimentary rocks do not form from crystals solidifying from magma; this process describes the formation of igneous rocks. The correct option for the process not involved in the formation of sedimentary rocks is option 2. Option 2 is the correct answer.
Step-by-step explanation:
Sedimentary rocks form through several processes except for crystals solidifying from magma. The correct options that represent the formation of sedimentary rocks include sediments becoming pressed or cemented together, sediments forming from solution, and water evaporating, leaving crystals behind.
These processes lead to the creation of clastic, chemical, and organic sedimentary rocks. The formation process excluded from the list, crystals solidifying from magma, actually describes the formation of igneous rocks which is an entirely different type of rock.
Therefore, the correct answer to the question, 'Sedimentary rocks form because of all of the following except ____.' is option 2) crystals solidifying from magma.