Costing

Well, it also depends on other factors too… Like what type of an industry it is… Service or Manufacturing? The type of market? Etc.

So let’s consider some other factors ALONG with a rapidly changing environment

1) Industry type – if service industry than target costing would be not very much suitable and so ABC and relevant costing may be better
2) high overheads and repetitive complex work – then surely ABC
3) highly competitive market with knowledgeable customers- than target costing would be more suited

So it entirely depends up on the scenario and other factors and we need to look at the broader picture. Most importantly how well you justify you justify your choice (that if the question requires an analysis and constructive response)

But even if you narrow it down i think “Relevant Costing” would be more suitable since only the relevant cost effected by the change in environment needs to be adjusted for.

I hope this helps.