Or E) amazed that a seemingly grown person cannot look into the subject matter for himself, specifically after he has already said that he has never done so and apparently has no intention of doing so unless what, I provide you links? How elementary is that? Are you really so stupid that you can't be bothered to find something out for yourself and would rather bicker from a standpoint of voluntary ignorance? THAT's why I won't give your lazy ass links. If you don't care enough about it to find out for yourself, I'm definitely not going to assume you would care about any of the information I might link to you.
I said I haven't thoroughly looked, implying that I did look. I found absolutely nothing except for a single sentence on wikipedia about kappa opioid receptors being dysphoric. Most the info I came across points to it causing sedation.