Appendix B page 274 The senior supplier represents the interests of those designing, developing, facilitating, procuring and implementing the project product. This role is accountable for the quality of the project product (and its components) delivered by the supplier(s) and is responsible for the technical integrity of the project. If necessary, more than one person may represent the suppliers. Depending on the particular customer/supplier environment, the customer may also wish to appoint an independent person or group to carry out assurance on the supplier’s products (e.g. if the relationship between the customer and supplier is a commercial one).

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chat GBT: While the senior supplier may work closely with those who will be developing the project's products (option 3), their primary responsibility is to ensure the technical integrity of the project. Therefore, while option 3 may have some representation from the senior supplier, it is not their primary focus. So if you have to choose two options, options 2 and 4 would be a better choice.