TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Negative growth rate results when birth rates fall even lower than death rates.

SOLUTION: What results when birth rates fall even lower than death rates?

PROBLEM: Population is an important level of organization in ecology and the unit of microevolution.

SOLUTION: What is an important level of organization in ecology and the unit of microevolution?

PROBLEM: After infecting a host, some viruses enter the inactive state of latency.

SOLUTION:
After infecting a host, what inactive state do some viruses enter?