Read the passage below. Then answer the question that follows.
Jamal sat down to put together his new desk. He reviewed the instructions and took all the pieces out of the box. The pieces of the desk were organized by Jamal on the floor. Then, he followed the instructions step by step until, an hour later, the desk was assembled.
Which of the following sentences revises the sentence in bold into active voice?
a) Jamal organized the pieces of the desk on the floor.
b) On the floor, the pieces of the desk were organized by Jamal.
c) The pieces of the desk had been organized by Jamal on the floor.
d) The pieces of the desk on the floor were organized by Jamal.