if I had to 'rank' them by how much it meant to me, it'd probably be physical and emotional tied for number 1, and then mental second because I can socialize with my boyfriend through skype, but nothing compares to being with him in person holding hands and "feeling" the love.
Probably mental the most. I'm somewhat of an introvert (more ambiverted though) and while I do enjoy and prefer my alone time, I still like to have contact with the outside world. So it's that stimulation that you listed that would soothe me a little bit and not make me feel so cut off or lonely.
For me it's actually A/B/C all together. I miss hugging her and giving her kisses, holding her hand. I also miss the emotional stuff like- bringing her coffees to work, and writing her love notes, sending her flowers, I took her on a picnic once and made lunch. The little stuff. Finally I miss being out in public together and being happy and smiling. I miss being so proud to introduce her to my friends and people I know as my girlfriend.
Maybe someday will miss all those about me. I'm not holding my breath though. Every day that passes is just another day closer to me never ever wanting her back.
Definitely a mix of all three because they all tie in together to me, but sometimes with one having a bigger edge over the others. For me personally, emotional is the one that's usually most significant.
Mental. I'm not a particularly emotional or affectionate person, but I need mental stimulation. I'm very introspective and can usually amuse myself quite well, but if I go extensive periods with little human contact, I usually crave conversation and interaction.