Which tactics are utilized in conducting a delay operation?

In conducting a delay operation, setting up obstacles and employing ambushes is a critical tactic used to slow down enemy forces. This type of operation is intended to disrupt the movement of an adversary, allowing friendly forces to withdraw or reposition while buying time. Obstacles may include physical barriers like mines, wire, or other fortifications designed to impede enemy advancement. Ambushes involve using surprise attacks against enemy units as they attempt to push through these obstacles, maximizing the effectiveness of friendly forces while minimizing the risk to their own during the retreat.

Direct assaults would not be a suitable tactic in a delay operation, as these typically involve engaging the enemy in a decisive confrontation rather than seeking to slow them down. Simply retreating does not leverage any tactical advantages and might lead to disorganization. Building fortifications could support a delay operation but is not a standalone tactic; it would generally complement the use of obstacles and ambushes. Therefore, the combination of these strategies in option B directly aligns with the objective of achieving a delay while ensuring effective withdrawal of forces.