Final answer:
The last Anglo-Saxon treasure was found in 2009 by metal detectorist Terry Herbert, known as the Staffordshire Hoard, none of the options provided in the question are correct.
Step-by-step explanation:
The last time Anglo-Saxon treasure was found was in 2009, and it was discovered by a metal detectorist named Terry Herbert. The treasure is known as the Staffordshire Hoard and it contains around 4,000 items, mostly war gear, thought to date back to the 7th or 8th century. This hoard is considered one of the largest finds of Anglo-Saxon gold and silver metalwork.
The options provided in the question do not accurately represent this event, as the options suggest findings in 2020 by a farmer, 1939 by an archaeologist, 1974 by a treasure hunter, and 1066 by William the Conqueror; however, none of these are correct with respect to the last find of Anglo-Saxon treasure.