Final answer:
The question is about the interpretation of topographic map contour lines and ensuring that a two-point code type is determinate by having a sufficient elevation difference between the scales. None of the provided answer choices is standard in topography.
Step-by-step explanation:
The question is related to topographic maps and the interpretation of contour lines. Specifically, it asks about a two-point code type that may be indeterminate unless the two scales exceed the third highest elevation by a certain amount. The given elevation references (10,000 ft., 5,000 ft., 2,000 ft., etc.) suggest that understanding contour intervals and map scales is essential for this problem. Given the options provided, none seem directly related to topographic map standards, but the question implies the need for a discernible elevation difference to avoid indeterminacy. Nonetheless, without context, the provided answer choices do not directly apply to the question as none corresponds to standard practices in topography.