Answer :
The error with the subject-verb agreement is:
Some people may think vegetarians don't get enough protein in their diets but a number of plant-based foods contains protein such as beans, nuts, and seeds.
The correct word is: "contain"
What is Concord?
This refers to the grammar rule that states that the subject of a sentence must agree with its verb.
Hence, we can see that the error with the subject-verb agreement is:
Some people may think vegetarians don't get enough protein in their diets but a number of plant-based foods contains protein such as beans, nuts, and seeds.
The correct word is: "contain"
Read more about subject-verb agreement here:
https://brainly.com/question/1835508
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