Material planning in the maintenance order is the process of determining the type, quantity, and availability of the materials required for carrying out the maintenance tasks. There are some considerations regarding material planning in the maintenance order, such as:

Material can be assigned at the operation level or the sub-operation level, but not at the order header level. This is because the material requirement is linked to the specific work that needs to be done in the order. Therefore, option A is incorrect1.

For stock material, you always need a reservation to ensure that the material is available when needed. A reservation is a request to the warehouse to keep a certain amount of material ready for withdrawal at a certain time. Therefore, option B is correct1.

A goods issue is the physical withdrawal of material from the warehouse. It can be entered for both planned and unplanned material in the maintenance order. Planned material is the material that is specified in the order before the actual execution of the work. Unplanned material is the material that is added to the order during or after the execution of the work. Therefore, option C is correct2.

The pick list is a document that lists all the materials that are required for a maintenance order. It can be printed after the order release, not before. The order release is the step that confirms that the order is ready to be executed and the materials can be withdrawn from the warehouse. Therefore, option D is incorrect3.

References: 1: Modelling Maintenance Processing - SAP Learning 2: [Manage Maintenance Orders - SAP Help Portal] 3: SAP S/4HANA Asset Management: Plants from a Maintenance … - SAP PRESS