How did Gaius Octavian acquire the name Augustus?

Julius Caesar gave him the name when he adopted him.

The name was given to all members of the Senate.

The Senate awarded him the title.

He became Gaius Augustus once he was married.

The Senate awarded him the title.

Explanation:

The Senate awarded Gaius Octavius Thurinus  the title  Augustus which meant "The illustrious One"because of his honorary actions in 27BCE

Gaius Octavius Thurinus  was the  adopted son of Julius Caesar which he took the name Gaius Julius Caesar after adoption and as stated in Ceaser's will.

Augustus, a Roman statesman and military leader was the first emperor of the Roman Empire, reigning from 27 BC till AD 14. His rule was known for peace and regarded as one of the most effective leaders in  history.

the andes or andean mountains (spanish: cordillera de los andes) are the longest continental mountain range in the world, forming a continuous highland along the western edge of south america. this range is about 7,000 km (4,300 mi) long, about 200 to 700 km (120 to 430 mi) wide (widest between 18° south and 20° south latitude), and of an average height of about 4,000 m (13,000 ft). the andes extend from north to south through seven south american countries: venezuela, colombia, ecuador, peru, bolivia, chile and argentina.

from wikipedia

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