intuition.
unfold foldBody_option.
unfold opt_pred in *.
destruct opt_a; destruct opt_b; intuition.
eapply comp_spec_ret; intuition.
Qed.

Theorem compFold_option_spec :
forall (A B : Set)(lsa : list A)(lsb : list B)(pre : A -> B -> Prop),
list_pred pre lsa lsb ->
forall (C D : Set){eqdc : EqDec C}{eqdd : EqDec D}(c1 : C -> A -> Comp (option C))(c2 : D -> B -> Comp (option D))(post : C -> D -> Prop) c d,
(forall c d a b, post c d -> pre a b -> comp_spec (opt_pred post) (c1 c a) (c2 d b)) ->
opt_pred post c d ->
comp_spec
(opt_pred post)
(compFold _ (foldBody_option _ c1) c lsa)
(compFold _ (foldBody_option _ c2) d lsb).