An agreement question tests whether a verb matches its subject, the person or thing doing what the verb says. Sort the forms by whether they go with it or they, setting tense aside. Then put who or what before the verb and cross out phrases and extra information around that subject. One thing takes a singular verb, and more than one takes a plural verb, so check with the shortened subject. A nearby noun doesn't decide the form unless it's the subject.
Hints
- Hint 1
Focus on the part of the sentence after “noted that.” Ask what does the underscoring to find the subject of the blank.
- Hint 2
Look at the phrase between the commas after “ocean acidification.” Ask about its role in the sentence: does it join another subject or give extra information?
- Hint 3
Read the subject and blank without the describing phrases. Can you replace that subject with it or they?
Step-by-step
Find the true subject
Step 1Sort the verb forms
Sort these forms of underscore by number to find the verb that matches its subject, the thing doing the underscoring. Which forms go with more than one? have underscored, underscore, and are underscoring are plural, so each goes with they. Now let's ask what underscores the urgency of coordinated international action; that will tell us which number the sentence needs.
- Step 2
Find the main noun
The noun group after noted that starts with the growing body of measurements. What does the underscoring: the body or one of the nouns describing it? Set aside of measurements documenting ocean acidification, which tells us what the body contains and what those measurements document. That leaves body as the main noun, which names one group even though the measurements are many.
- Step 3
Check whether the subject gains another part
Does along with projections of accelerating Arctic ice loss add a second subject? The phrase is extra information between commas; along with doesn't join subjects the way and does. The projections don't change the subject's number, so we can read the sentence without that whole phrase. The words about ice loss describe the projections, which means neither projections nor loss controls the blank.
- Step 4
Match the singular helper
Shrink the growing body to it: it has underscored. A verb with a helper shows number in that helper, and has is singular, so this form agrees with the subject and completes the clause. Choice A.