= Solution
The operator $ia\bar\psi\sigma^{\mu\nu}\gamma^5\psi F_{\mu\nu}$ is the relativistic <fermion electric dipole moment operator>. Its nonrelativistic limit contains $\mathbf S\cdot\mathbf E$: <spin angular momentum> is an <axial vector>, whereas the <electric field> is a polar vector. It is consequently odd under <parity symmetry in quantum field theory>. Both the pseudotensor fermion bilinear and the <electromagnetic field tensor> are odd under <charge conjugation>, so their product is even. Therefore
$$
\boxed{P:-1,\qquad C:+1,\qquad CP:-1.}
$$
The <CPT theorem> then makes it odd under <time-reversal symmetry>. Such an interaction can arise only from <CP violation>. The <Cabibbo-Kobayashi-Maskawa matrix> therefore induces a nonzero Standard Model electric dipole moment at sufficiently high loop order, but its flavor structure and loop suppressions make the result extraordinarily small.
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