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?
Explanation
Context: The sentence uses em dashes to set off a parenthetical: "—in this case, the porous rocks of the hills around Hot Springs—." The blank falls inside this em dash structure; the closing em dash after "Springs" ends the parenthetical, and "to" continues the main clause.
Answer: C) Springs—to
Why? The sentence opened with "—" before "in this case," and needs a matching "—" to close the parenthetical before resuming the main clause with "to collect in a subterranean basin."
Traps:
- A) Springs to → missing the closing em dash; the parenthetical opened by the em dash is never closed, leaving the sentence structurally incomplete
- B) Springs: to → a colon cannot close an em dash parenthetical; the em dash must be closed with another em dash
- D) Springs, to → a comma cannot close an em dash parenthetical; the em dash must be matched with another em dash