a quasi-periodic oscillations (QPO). The QPOs evolve along with the spectral states of the accretion disc, starting with low frequencies in LH, increasing as the luminosity increases, and reaches highest value before disappearing in the HS state [@cdnp08; @st09; @ndmc12; @nrs13]. Interestingly, although QPO frequency increases as the accretion disc moves from LH to intermediate states, but no QPO was detected during ejection of relativistic jets [@nrs13; @rn13] which suggests that, probably the part of the disc responsible for QPO is entirely ejected as relativistic jets. This conversely also suggests that, the inner part of the disc is responsible for QPOs and is also the base of the jet. Accretion disc models which are invoked to explain the accretion-ejection phenomena around black hole candidates, should at least address the connection between spectral states, QPO evolution and the evolution of jets, apart from matching the luminosities radiated by AGNs and microquasars.

There are various accretion disc models in the literature. We know that, matter crosses the horizon with the speed of light ($c$) and circular orbits cannot exist within the marginally stable orbit ($3r_g$). So the inner boundary condition for accretion onto black hole is necessarily transonic, as well as, sub-Keplerian, 