Why has realist scholar Stephen Walt warned against adopting a post-structuralist approach?

A. Post-structuralism is too concerned with human rights.
B. Post-structuralism does not focus enough on ‘the state’ as the primary category of political organisation.
C. He argues that post-structuralism is, in its current form, unable to comprehend world politics and security studies and instead focuses too much on being a critical approach.
D. Post-structuralism does not place enough focus on civil liberties and human rights.