What does it mean when your pokemon shakes before battle

As mentioned above, Pokemon with Affection levels high enough to have a potential impact on battle will begin to shake/shudder from side to side when sent out in battle. If you see this happen, you'll also likely see messages appear randomly at certain points in battle

Explanation:

answer; i believe the correct answer is (a) the correlation between the cause variable and outcome variable is zero;

answer; motor learning;