How do the details about Guyana reveal the author's purpose?

They show that the author wants to inform readers by describing the old sugar estates.

Explanation:

In the excerpt, the author describes that he went to Guyana to find the fate of his house.

Upon arrival, the sight of the lush canes made him realize that sugar was the main crop on which this country depended. Sugar was the main crop on which the business of the country relied. Such lush crops of sugar were one of the main reasons that why sugar was inexpensive in Guyana.

The answer is indeed B