  We consider the possibility that after operations at the LHC and e^+e^-
Linear Colliders a Higgs boson will be discovered, but no signal of New Physics
will be found (Standard-Model-like scenario). This can occur in the Standard
Model (SM) as well as in other models, including the Two-Higgs-Doublet Model
(2HDM), the MSSM, etc. Experiments at a Photon Collider can resolve these
cases.
  In this paper we compare the SM and the 2HDM~(II). In the analysis we use as
independent quantities the ratios, to the SM values, of couplings of the
observed Higgs boson to gauge bosons, and to up and down-type quarks (basic
couplings). We derive a relation between these ratios within the 2HDM~(II), a
pattern relation. With the aid of this relation, different possible
realizations of an SM-like scenario are found. For these realizations, we
calculate the loop couplings of the Higgs boson with \gamma\gamma and Z \gamma,
and also with gluons, taking into account the expected accuracy in the
measurements of the basic couplings. The obtained deviation of the two-photon
width from its SM value is generally higher than the expected inaccuracy in the
measurement of \Gamma_{\gamma \gamma} at a Photon Collider. The result is
sensitive to the parameters of the Higgs self interaction.
