Final answer:
SAS uses the CONCATENATE function to append observations from one dataset to another.
Step-by-step explanation:
The combining dataset technique that SAS uses to append observations from one dataset to another is CONCATENATE.
The CONCATENATE statement in SAS combines two or more datasets that have the same structure, stacking them one after another. The resulting dataset contains all the observations from the input datasets.
For example, if you have two datasets: Dataset A with 100 observations and Dataset B with 150 observations, using the CONCATENATE statement in SAS would result in a new dataset that contains 250 observations.