What is the correct order of terms from the smallest to largest amount of resources?

The correct sequence is based on the classification and quantification of geological resources as they transition from the most certain, recoverable quantities to larger estimates that encompass less certain quantities.

Proven reserves represent the most reliable category, as they consist of quantities that are known to be recoverable under existing economic and operational conditions. Following that, the reserve base is larger since it accounts for the total amount of that resource that has been discovered and is recoverable but doesn’t necessarily have the same level of certainty and accessibility as proven reserves.

Next in the sequence is resources, which represent a broader category that includes all quantities of material where there is some level of assessed recovery potential, whether it's proven or less certain. Lastly, the resource base encompasses all identified and inferred quantities, hence being the most extensive. It includes everything at a broader level, even those which may not technically be classified as recoverable.

This order illustrates a clear understanding of resource management as it represents a continuum from known, recoverable assets to a total estimate that encompasses the potential of the resource, emphasizing the uncertainty that increases with broader classifications.