To declare an explicit cursor in the PL/SQL language, the user needs to know how to write PL/SQL code and the concept of cursors.

An explicit cursor is a cursor that is defined and managed by the user. It requires the user to declare a cursor variable that references the cursor and then define the SQL statement that will be executed when the cursor is opened.

With that in mind, the correct answer is:

B. In the PL/SQL declaration section

The declaration section of a PL/SQL block is where variables, constants, and cursors are declared. In this section, the user can declare the explicit cursor variable by specifying its name, data type, and the query to be executed. Once the cursor variable is declared, the user can then open, fetch, and close the cursor in the body section of the block.

Option A is incorrect because the PL/SQL working storage section does not exist.

Option C is incorrect because the PL/SQL body section is where the logic of the block is implemented, not where the cursor is declared.

Option D is incorrect because the PL/SQL exception section is where exception handling code is written.

Option E is incorrect because one of the above options (Option B) is the correct answer.

Therefore, the answer is: B. In the PL/SQL declaration section.