This is the relevant information: The lowest natural temperature ever directly recorded at ground level on Earth is − 89.2 ° C (− 128.6 ° F; 184.0 K) at the Soviet Vostok Station in Antarctica on July 21, 1983 by ground measurements.
This justifies what answer for what question? Q & A: 
Passage: The lowest natural temperature ever directly recorded at ground level on Earth is − 89.2 ° C (− 128.6 ° F; 184.0 K) at the Soviet Vostok Station in Antarctica on July 21, 1983 by ground measurements.

Question: Based on this passage, where was the lowest temperature ever recorded on earth?
the Soviet Vostok Station in Antarctica