Group in which any two normal subgroups are comparable

Definition
A group is said to be a group in which any two normal subgroups are comparable if any two normal subgroups of the group can be compared, or in other words, if its lattice of normal subgroups is a totally ordered set. In other words, given any two normal subgroups of the group, one of them must lie completely inside the other.

Facts

 * Symmetric groups are normal-comparable