Star Trek: Mind Meld Mystery Cache

Caching: The finder's frontier.  These are the voyages of the caching explorers.  Their life-long mission: to explore strange new towns, to seek out new caches and new hiding spots, to boldly go where no muggle has gone before.

This Star Trek Geoart is a tribute for Trekkies and non Trekkies all around. Answer the questions to find the final coordinates for each cache in the series. Cache is not at the posted coordinates. Enjoy!

Mind Meld

Several Star Trek episodes featured Leonard Nimoy's character, Spock, performing a mind meld.  The Vulcan mind meld was a telepathic link between two individuals, allowing for the exchange of thoughts, thus in essence allowing the participants to become one mind.  It was a psi-onic technique for "synaptic pattern displacement". Normally it was employed only by Vulcans. It was a deeply personal thing, part of the private life, and generally not used on aliens, although cases were known where the mind meld was initiated between a Vulcan and a non-Vulcan. Those in a meld shared consciousness in a kind of gestalt. -memory-alpha.org

QUESTION FOR FINAL COORDINATES: In what episode of The Original Series did Spock's Vulcan mind meld make its first appearance?

A: The Empath - N39 25.515 W087 25.845

B. Man Trap - N39 25.454 W087 25.741

C. Dagger of the Mind - N39 25.285 W087 25.916

D. Arena - N39 25.319 W087 25.124