I can't find any logical relationship in this grid! Could someone help me, please?

4x4 grid

and choices are

A. 8

B. 6

C. 5

D. 4

This book is the source of the puzzle. The translation of its title is Enhancing the intelligence and educational ability of children and adolescents

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    $\begingroup$ Hi, and welcome to Puzzling SE! On this site, clearly citing the source is a minimum requirement for puzzles that aren't of your own making. You can also take the tour to get to know the site a bit better. Happy Puzzling! $\endgroup$ – Bass Jul 15 '18 at 19:55
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    $\begingroup$ That's not quite what's meant by "citing the source". The point is that we need to know where the question comes from. While we're at it: do you have the permission of whoever made the puzzle to reproduce it here? $\endgroup$ – Gareth McCaughan Jul 15 '18 at 20:11
  • $\begingroup$ @GarethMcCaughan I understand, but I don't know anything about this puzzle. I just have this piece of the image. It has been circulated among some people and I don't know its origin. $\endgroup$ – 01000110 Jul 15 '18 at 20:22
  • $\begingroup$ Ah. Then I think we have to close it; sorry! (For all we know, it may be a copyright violation, which would be illegal; for all we know, it may be a still-ongoing competition, which we have a site-wide policy against.) $\endgroup$ – Gareth McCaughan Jul 15 '18 at 21:21
  • $\begingroup$ Putting this on hold for the reason described above. OP, if you do find out where it's from and establish that it's OK for it to be reproduced here, it can be reopened. (Apologies for the misleading close reason that will appear in a yellow box below the question; we have a very limited number of reason-descriptions and they don't really cover all the possibilities.) $\endgroup$ – Gareth McCaughan Jul 15 '18 at 21:24