When scaling resources in a data pipeline, it is important to consider the size of the data being processed, the processing time required for the data, and the cost of scaling resources. Scaling resources based on the workload ensures that the pipeline can handle the data volume and processing requirements while optimizing costs. Option A is correct because the size of the data affects the processing and storage requirements. Option B is correct because the processing time affects the performance and throughput of the pipeline. Option C is correct because scaling resources can incur additional costs, and it is important to balance performance with cost considerations.