  In this paper, we present unique observations of a blowout coronal jet that
possibly triggered a two-ribbon confined C1.2 flare in a bipolar solar active
region NOAA 12615 on 2016 December 5. The jet activity initiates at
chromospheric/transition-region heights with a small brightening that
eventually grows in a larger volume with well developed standard morphological
jet features, viz., base and spire. The spire widens up with a collimated
eruption of cool and hot plasma components, observed in the 304 and 94 A
channels of AIA, respectively. The speed of the plasma ejection, which forms
the jet's spire, was higher for the hot component (~200 km/s) than the cooler
one (~130 km/s). The NLFF model of coronal fields at pre- and post-jet phases
successfully reveal opening of previously closed magnetic field lines with a
rather inclined/low-lying jet structure. The peak phase of the jet emission is
followed by the development of a two-ribbon flare that shows coronal loop
emission in HXRs up to ~25 keV energy. The coronal magnetic fields rooted at
the location of EUV flare ribbons, derived from the NLFF model, demonstrate the
pre-flare phase to exhibit an "X-type" configuration while the magnetic fields
at the post-flare phase are more or less parallel oriented. The comparisons of
multi-wavelength measurements with the magnetic field extrapolations suggest
that the jet activity likely triggered the two-ribbon flare by perturbing the
field in the interior of the active region.
