Final answer:
The verb agreement for the subject in question is 'are'.
Step-by-step explanation:
The subject of the question is Art. The question is asking about the verb agreements in a pair of paintings that are being referred to as 'we've heard so much about.'
When referring to a pair of paintings, the verb agreement should be plural. In this case, the correct phrasing would be 'there are a pair of paintings we've heard so much about.'
Therefore, the correct verb agreement for the subject is are.