$.$According to the maturity model of e$-$government development proposed by

Layne and Lee $(2001),$ which option best captures the essence of the different

stages?

$($A$)$ Transaction: The USPS website allows users to schedule package pickups and

track shipments

$($B$)$ Vertical integration: NYC$311$ connects with various government systems to

streamline and improve the user experience

$($C$)$ Horizontal integration: NJ$.$gov website brings together various resources,

$3$

services, and information from different government departments and agencies to

provide a one$-$stop$-$shop

$($D$)$ All of the option