Why was the marina district, san francisco, heavily damaged in the 1906 and 1989 quakes?
a. shaking was no more extensive than elsewhere in the city, but the whole district burned following each quake.
b. the epicenters of both quakes were right under the district.
c. liquefaction and foundation failures were common.
d. the area is built on consolidated rock, causing the shaking to be amplified.

Option: C. Liquefaction and foundation failures were common.

Explanation:

The Marina District in San Francisco massively damaged in the 1906 and 1989 because of the earthquakes. The buildings in the area built above the land filled with mud and sand. The earthquake creates a situation of liquefaction that led to damaging the foundation of buildings. Soil loses its strength and stiffness in response to the shakes it gets because of the quake.