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.

Which valuation tool is recommended to be used if the goal is to make comparisons of three or more variables over time?
Option A:Heat map
Option B:Bubble line chart
Option C:Scatter plot matrix

Answer: B