Reading quiz: what is a good colormap?

A colormap is used to assign colors to contour plots, surface plots, etc. In many tools, the default colormap is "rainbow" (called "jet" in MATLAB). In the last decade, scientists have realized that the rainbow colormap is not so good for scientific visualization.

The quiz consists in reading the following two blog posts, then answer the question below.

https://blogs.mathworks.com/steve/2014/10/20/a-new-colormap-for-matlab-part-2-troubles-with-rainbows/

https://mycarta.wordpress.com/2012/05/12/the-rainbow-is-dead-long-live-the-rainbow-part-1/