Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

A line chart with two variables—for example, revenues and earnings per share—is best suited for visualizing:
Option A:the joint variation in the variables.
Option B:underlying trends in the variables over time.
Option C:the degree of correlation between the variables.

Answer: B