Which reason explains why this grievance
included in the Declaration?

The correct answer is B. The colonists could export goods only to Britain.

Explanation

One of the reasons that motivated the colonists to became independent from Great Britain was that Great Britain imposed unfair conditions to the colonist. One of these was that the colonists could not sell their products to other nations, and therefore they could be exported to Great Britain. This is explain in the quote "For cutting off our Trade with all parts of the world". According to this, the correct answer is B. The colonists could export goods only to Britain.

i would go with the last one