The MC95RW sensor provides a strong response from Extremely Low Frequency (ELF) through Very Low Frequency (VLF), with a very strong maximum at resonance near 1.6 kHz. The resonant frequency (usually near 1.6 kHz) may vary considerably due to individual assembly variations and the complex output impedance the sensor output is connected to. So the calibration curve (Vo/field) may differ from your results due to different output impedances at resonance and higher frequencies.
The MC95RW has 3-wire output and connector for wire-to-board or wire-to-wire applications. Twisting the wires together minimizes pickup of stray fields. You can use the 3-wire connector (MTA-100 IDC) attached to ends of the wires, or you can cut it off.
The calibrated voltage output is measured between the red and yellow wires. The green wire is a center-tap, it is not necessary to use the green wire, it provides 1/2 of the voltage output to either end of the coil (to the red or to yellow wire).
If soldering the wires to a connector or coaxial or other transmission line: normally the red and yellow wires are used. The red or yellow can be soldered to the center conductor, and the other (red or yellow) to the outer conductor of the coax.