Final answer:
The primary earthquake hazard among the given options is 2. ground shaking.
Step-by-step explanation:
The primary earthquake hazard among the given options is 2. ground shaking. Ground shaking refers to the vibrations and movements of the Earth's surface during an earthquake. It is caused by the release of energy when the tectonic plates in the Earth's crust slide past each other.
The shaking can cause buildings and infrastructure to collapse, leading to significant destruction and loss of life.