The KSP2907A is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, base, and collector leads. The KSP2907AC transistor (with suffix "C") is the center collector version of the KSP2907A. Here is an image showing the pin diagram of this transistor.
Complementary NPN transistor
The complementary NPN transistor to the KSP2907A is the KSP2222A.