To find the expression that represents \( L(x) - M(x) \), we will subtract \( M(x) \) from \( L(x) \).
Given: \[ M(x) = 4x^2 - 8x + 17 \] \[ L(x) = 5 - 2x^2 \]
Now, let's calculate \( L(x) - M(x) \): \[ L(x) - M(x) = (5 - 2x^2) - (4x^2 - 8x + 17) \]
Distributing the negative sign in front of \( M(x) \): \[ = 5 - 2x^2 - 4x^2 + 8x - 17 \]
Now combine like terms:
- Combine the \( x^2 \) terms: \(-2x^2 - 4x^2 = -6x^2\)
- The \( x \) term is \( 8x \).
- Combine the constant terms: \( 5 - 17 = -12 \).
Putting it all together, we have: \[ L(x) - M(x) = -6x^2 + 8x - 12 \]
Therefore, the expression that represents \( L(x) - M(x) \) is: \[ \boxed{D. \ -6x^2 + 8x - 12} \]