Final answer:
The sentence in question is a declarative sentence because it makes a statement and ends with a period.
Step-by-step explanation:
The sentence 'Rumor had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.' is a declarative sentence.
A declarative sentence is used to make a statement or provide information about a particular subject. It ends with a period. This type of sentence is different from interrogative, imperative, and exclamatory sentences because it does not ask a question, give a command, or express strong emotion with an exclamation point.