Nhận biết (M1)

Studying advertisements for defunct amusement parks, menus from nineteenth-century restaurants, and handbills promoting long-forgotten political candidates may seem like a frivolous pursuit, but ephemeral objects like these are useful as __________ cultural change, revealing shifts in norms, values, and concerns that traditional objects of historical inquiry may not.

Which choice completes the text with the most logical and precise word or phrase?

• A.

  alternatives to

• B.

  conjectures about

• C.

  indices of

• D.

  pretexts for