Final answer:
Increasing intervals of a function indicate where the function's output is growing as the input increases. For a linear function, this would be where the coefficient of x is positive, signifying an upward slope.
Step-by-step explanation:
The student's question pertains to identifying intervals over which a function is increasing. To address this, one must analyze the slope of the function or its derivative if dealing with a calculus problem. An increasing function will have a positive slope or a positive derivative. Without the specific function provided, we must rely on generic criteria for increasing intervals.
For linear equations, such as those mentioned in options A, B, and C from Practice Test 4, identifying the interval of increase is straightforward. If the coefficient of x is positive, the line is increasing. Based on this, if the function is similar to line A described as increasing, and considering there are no indications of changes in slope or any non-linear behavior, the correct intervals would be those where the slope remains positive throughout.