Which one of the following statements is true regarding paragraphs?

a. the topic of a paragraph is always placed in the first sentence.
b. a paragraph with two main topics is called a complex paragraph.
c. a topic sentence should not be placed in the middle of a paragraph.
d. a paragraph should have one main topic.

When they reached the door of the lonely house and stopped to unlock it, and the cat came to purr loudly, and rub against them, a deserted p***y, indeed, but fat with young robins, sylvia whispered that this was a beautiful place to live in, and she never should wish to go home. the description of the house in this excerpt gives an example of