Which is easier to write, a black pen or a blue pen?

It seems that there was a test before ~ ~ that is, the same person wrote the same test paper with blue-black pen, black pen and pure blue pen respectively ~ ~ The results were shown to different teachers ~ ~ The score written with blue-black pen was always high ~ ~ Then it was written with pure blue pen ~ Finally it was black ~ ~

I think writing a large area with black pen will make people feel bloated and uncomfortable after reading it.