What connection does the author make between magma and its cooling rate? A. Magma that cools quickly creates igneous rocks that are softer. B. Magma that cools slowly creates igneous rocks that are more valuable. C. The magma's cooling rate determines the size of crystals that are formed. D. The magma's cooling rate determines whether sedimentary or igneous rocks form.

## Step 1<br />The problem is asking us to identify the correct connection between magma and its cooling rate. The options provided are:<br />A. Magma that cools quickly creates igneous rocks that are softer.<br />B. Magma that cools slowly creates igneous rocks that are more valuable.<br />C. The magma's cooling rate determines the size of crystals that are formed.<br />D. The magma's cooling rate determines whether sedimentary or igneous rocks form.<br /><br />## Step 2<br />We need to evaluate each option based on our knowledge of geology.<br /><br />## Step 3<br />Option A suggests that magma that cools quickly creates softer igneous rocks. However, this is not accurate because the cooling rate of magma does not determine the hardness or softness of the resulting igneous rock.<br /><br />## Step 4<br />Option B suggests that magma that cools slowly creates more valuable igneous rocks. This is also not accurate because the value of igneous rocks is not determined by the cooling rate of the magma.<br /><br />## Step 5<br />Option C suggests that the magma's cooling rate determines the size of the crystals that are formed. This is accurate because the cooling rate of magma does indeed affect the size of the crystals that form. Slow cooling allows for larger crystal formation, while rapid cooling results in smaller crystals.<br /><br />## Step 6<br />Option D suggests that the magma's cooling rate determines whether sedimentary or igneous rocks form. This is not accurate because the type of rock that forms is determined by the composition of the magma, not its cooling rate.