Positive correlation means as you print more pages, you use more ink as opposed to negative correlation: you print more pages and use less ink.  This is definitely a positive correlation: the more you print, the more ink you use.

So that leaves answers (1) and (2).

The word causal means one variable causes another…since an increase in the number of pages printed will cause more ink to be used, it is positive correlation and causal.
That’s it — 2 more points!

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