To expand the expression \((3x - 2y)^2\), we can use the formula for the square of a binomial:
\[ (a - b)^2 = a^2 - 2ab + b^2 \]
In this case, \(a = 3x\) and \(b = 2y\). Applying the formula, we have:
\[ (3x - 2y)^2 = (3x)^2 - 2(3x)(2y) + (2y)^2 \]
Calculating each term:
- \((3x)^2 = 9x^2\)
- \(-2(3x)(2y) = -12xy\)
- \((2y)^2 = 4y^2\)
Putting it all together:
\[ (3x - 2y)^2 = 9x^2 - 12xy + 4y^2 \]
Now looking at the options provided, the expression we derived matches:
D. \(9x^2 - 12xy + 4y^2\)
So the answer is D.