  This is the second installment in a series of papers applying descriptive set
theoretic techniques to both analyze and enrich classical functors from
homological algebra and algebraic topology. In it, we show that the \v{C}ech
cohomology functors $\check{\mathrm{H}}^n$ on the category of locally compact
separable metric spaces each factor into (i) what we term their definable
version, a functor $\check{\mathrm{H}}^n_{\mathrm{def}}$ taking values in the
category $\mathsf{GPC}$ of groups with a Polish cover (a category first
introduced in this work's predecessor), followed by (ii) a forgetful functor
from $\mathsf{GPC}$ to the category of groups. These definable cohomology
functors powerfully refine their classical counterparts: we show that they are
complete invariants, for example, of the homotopy types of mapping telescopes
of $d$-spheres or $d$-tori for any $d\geq 1$, and, in contrast, that there
exist uncountable families of pairwise homotopy inequivalent mapping telescopes
of either sort on which the classical cohomology functors are constant. We then
apply the functors $\check{\mathrm{H}}^n_{\mathrm{def}}$ to show that a seminal
problem in the development of algebraic topology, namely Borsuk and Eilenberg's
1936 problem of classifying, up to homotopy, the maps from a solenoid
complement $S^3\backslash\Sigma$ to the $2$-sphere, is essentially hyperfinite
but not smooth.
  In the course of this work, we record Borel definable versions of a number of
classical results bearing on both the combinatorial and homotopical
formulations of \v{C}ech cohomology; in aggregate, this work may be regarded as
laying foundations for the descriptive set theoretic study of the homotopy
relation on the space of maps from a locally compact Polish space to a
polyhedron, a relation which embodies a substantial variety of classification
problems arising throughout mathematics.
