Curved lines or straight lines can function as trend lines on a graph.
Answer: Option C
Step-by-step explanation:
In general, trend refers to a pattern or behavior to represent a set of data in terms. In statistical point of view, trend lines are used in graph to represent a set of data values in terms of function in order to determine a relation between them for better understanding. The trend line can either be a curved line or a straight line which shows the direction on which the data travels.