Life cycle mcq

I know that all costs are accounted for in the lifecycle costing over the life of the product but it says that sunk costs are also included (which I thought does not).

There is an MCQ question in kaplan kit (Q26) which states that:

> Lifecycle costing takes into account all costs incurred in a product lifecycle with exception of sunk costs incurred on research and development

However, this statement is not correct.

There is no explanation given for this in the answers!