Located on the northeast coast of Northern Ireland, the Giant's Causeway is an area of about 40,000 interlocking basalt columns. The site , which was formed by an ancient volcanic fissure eruption, attracts thousands of tourists and geologists each year. Visitors marvel at the near-perfect hexagonal pillars that stretch from the cliffs into the sea.
Which choice is the most grammatically correct punctuation of the underlined portion?
- , which was formed by an ancient volcanic fissure eruption, attractsAnswer
- B, which was formed by an ancient volcanic fissure eruption attracts
- C; which was formed by an ancient volcanic fissure eruption, attracts
- D, that was formed by an ancient volcanic fissure eruption, attracts
Answer
The correct answer is the option that uses the pronoun 'which' and sets off the nonessential relative clause with commas both before and after: ', which was formed by an ancient volcanic fissure eruption, attracts'.
The relative clause describing the volcanic origin of the site is nonessential because 'the site' is already identified as the Giant's Causeway. Nonessential clauses must be set off by a pair of commas. The correct option correctly includes both the opening comma after 'site' and the closing comma after 'eruption'.
Step-by-Step Solution
Key Concept
Nonessential (nonrestrictive) clauses add extra details to a sentence and must be set off by commas. Restrictive clauses are essential to the meaning and must not be separated from their referents by commas.