Igneous rocks form when minerals crystallize from cooling magma or lava. The more slowly the magma or lava cools, the larger the crystals are able to grow.

The images below show two different igneous rocks. Examine the images, and then answer the question that follows.
Assuming that these images are shown at the same scale, which of the following can be concluded based on the information above?
A.
Rock X formed from magma; rock Y formed from lava.
B.
Rock Y cooled more slowly than rock X.
C.
Both rocks cooled at the same rate.
D.
Rock X cooled more slowly than rock Y.