Final answer:
The correct answer is linear, constant. In a linear function, the value of y increases by a constant amount each time x increases by a fixed value.
Step-by-step explanation:
The correct answer is a) Linear, constant.
In a linear function, the value of y increases by a constant amount each time x increases by a fixed value. In this case, y increases by 3 each time x increases by 1. This means that the relationship between x and y is a constant increase, which is characteristic of a linear function.
An exponential function, on the other hand, has a constant ratio of change. In the given scenario, y increases by 3, which is not a constant ratio since it does not depend on the value of x. Therefore, the correct answer is linear, constant.