Final answer:
The rule that represents Alan's age as a function of his brother's age is A = 2 * B - 3.
Step-by-step explanation:
The rule that represents Alan's age as a function of his brother's age is A) A = 2 * B - 3.
To find this rule, we examine the answer choices and look for the one that expresses the relationship between Alan's age (A) and his brother's age (B). Only option A matches the required form of the equation, with A equal to 2 times B minus 3. Therefore, the correct answer is A) A = 2 * B - 3.