Answer:
A) the discovery and excavations of Herculaneum and Pompeii
Explanation:
Different from a book or a drawing which can show us just a part of the building or city, and we must use our imagination to think and feel how it was the real construction, the excavations of Herculaneum and Pompeii provide us the factual prove, the real structure that was described in books and scriptures, and based on the theoretical ideas, we can make a comparison and found out the truth.
Freedom of speech (i don't know whats your question exactly).
hope this helps :)
His first invention was a <span>phonograph </span>
