The O a. lower, higher O b. higher, more O c. flattest, lower O d. steepest, more constant the curvature of the Isoquant, the the substitution between K and L.

To analyze the relationship between the curvature of the Isoquant and the substitution between capital (K) and labor (L), let's break down the concepts involved:

1. Understanding Isoquants: Isoquants represent combinations of inputs (capital and labor) that yield the same level of output. The shape of an isoquant indicates the rate at which one input can be substituted for another while keeping output constant.

2. Curvature and Substitutability:

   • A flatter isoquant suggests that capital and labor can be easily substituted for each other, indicating a higher rate of substitution.
   • A steeper isoquant suggests that the inputs are not as easily substituted, indicating a lower rate of substitution.

3. Interpreting Options:

   • Option a (lower, higher) seems to imply that with lower curvature, there would be higher substitution, which contradicts the analysis.
   • Option b (higher, more) suggests higher curvature implies more substitution, which is also contradictory.
   • Option c (flattest, lower) suggests that the flattest isoquant corresponds to lower substitution, which is incorrect.
   • Option d (steepest, more) suggests that a steep isoquant indicates more constant (or lower) substitution, and this aligns well with the analysis of curvature.

Final Interpretation: Option d: steepest, more constant accurately represents the relationship where higher curvature implies a lower rate of substitution between K and L. In summary, as the curvature of the isoquant increases (becomes steeper), the ability to substitute between inputs decreases, reflecting less flexibility in replacing one input with another.