D

To find the dimensions of the constants in the strong nuclear force equation \( F = \frac{Ce^{-kr}}{r^2} \), we need to analyze the components one by one.

**Step 1: Analyzing the force equation:** \( F \) has dimensions of force, which is \( [F] = M L T^{-2} \). The right-hand side must also equate to this dimension.

**Step 2: Analyzing the term \( \frac{Ce^{-kr}}{r^2} \):**
- The term \( r^2 \) clearly has dimensions of length squared, \( [r^2] = L^2 \). Therefore, the dimensions of \( \frac{C}{r^2} \) must also equal \( M L T^{-2} \):
\[ [C] \cdot L^{-2} = M L T^{-2} \]
Rearranging gives
\[ [C] = M L^3 T^{-2} \]

**Step 3: Analyzing the exponential term \( e^{-kr} \):**
To be dimensionless, \( kr \) must also be dimensionless. Thus, \( [k] \cdot [r] = 1 \). Hence,
\[ [k] = L^{-1} \]

**Final Dimensions:**
- The dimensions of \( C \) are concluded to be \( M L^3 T^{-2} \).
- The dimensions of \( k \) are \( L^{-1} \).

Therefore, the answer lies in analyzing the combined components, leading us to choose the option that corresponds to \( M L^3 T^{-2}, L^{-1} \) correctly. Hence, the correct answer among the options is D.