This would be considered an imperative sentence.
<span>Schlosser next focuses on the safety not just of factory workers in the meatpacking industry, but of the meat itself that that industry produces. Schlosser notes, throughout the chapter, that it is actually quite difficult to track the source of food-borne pathogens in the United States. There are several reasons for this, some more preventable than others: a great deal of meat is produced in this country; government oversight in meatpacking plants is rather low; and meat production is a complex system with many inputs, making cause and effect hard to determine.</span>
Hello, so the verb is the action and the compound subject is going to be
our second subject in the sentence. To distinguish whether it is
corresponding or not we are going to make sure that it is in the right tense, person, etc.
So lets look at our options
Our
first sentence has the first subject plural but not the second subject,
and an improper use of the verb making this sentence grammatically incorrect.
Our second sentence the verb and compound correspond correctly so no mistakes here.
The third sentence we are distinguishing whether we use begun or began. Began is past tense and begun is past participle.
The last sentence is grammatically incorrect because the action/verb 'stores' does not correspond with our compound subject.
So that leaves us with the answer being B.
I hope I helped! If you have any other questions or would like further explanation please let me know! :)