  The cross section of the exclusive $\eta$ electroproduction reaction $ep\to
e^\prime p^\prime \eta$ was measured at Jefferson Lab with a 5.75-GeV electron
beam and the CLAS detector. Differential cross sections
$d^4\sigma/dtdQ^2dx_Bd\phi_\eta$ and structure functions $\sigma_U =
\sigma_T+\epsilon\sigma_L, \sigma_{TT}$ and $\sigma_{LT}$, as functions of $t$
were obtained over a wide range of $Q^2$ and $x_B$. The $\eta$ structure
functions are compared with those previously measured for $\pi^0$ at the same
kinematics. At low $t$, both $\pi^0$ and $\eta$ are described reasonably well
by generalized parton distributions (GPDs) in which chiral-odd transversity
GPDs are dominant. The $\pi^0$ and $\eta$ data, when taken together, can
facilitate the flavor decomposition of the transversity GPDs.
