Answer: A
Step-by-step explanation:
For II, when the numerator is expanded, it contains terms of ab and a^2 which makes it a quadratic function, not an algebraic function.
For III, tricky one. The a can be cancelled out in the numerator and denominator and the resulting fraction is (b-3)/3. However, this can be further simplified to 1/3b - 1, which makes it not an algebraic fraction anymore.