The forty-seven geothermal springs of Arkansas' Hot Springs National Park are sourced via a process known as natural groundwater recharge, in which rainwater percolates downward through the earth-in this case, the porous rocks of the hills around Hot __ collect in a subterranean basin. Which choice completes the text so that it conforms to the conventions of Standard English? A. Springs to B. Springs: to C. Springs-to D. Springs, to

## Step 1<br />The sentence is discussing the process of natural groundwater recharge, which is how the geothermal springs of Arkansas' Hot Springs National Park are sourced. The sentence is explaining this process in detail, so it needs to be separated from the rest of the sentence.<br />## Step 2<br />The colon is used to introduce a list, an explanation, or an example. In this case, the colon is used to introduce an explanation of the process of natural groundwater recharge.<br />## Step 3<br />The colon is placed after "Springs" and before "to", which is the beginning of the explanation of the process. This is the correct usage of a colon in English grammar.