Final answer:
The simplified form of the expression is (x^3)(y^12).
Step-by-step explanation:
The simplified form of the expression is C. (x^3)(y^12).
To simplify the expression, we combine the exponents of like variables.
In this case, both variables x and y have exponents, so we can combine them:
x^4 * y = x^(4+1) * y^1 = x^3 * y^12
Therefore, the simplified form of the expression is (x^3)(y^12).