Can learners mix 19th and 20th century Core Content?

Learners should study all the Core Content in either Option A, The 19th century, or Option B, The 20th century.

However, learners can study a mixture of 19th and 20th-century questions in Section A of Paper 1. Learners can also answer 20th-century questions on Paper 2 or vice versa. The most common way of mixing coverage is for those teaching the 20th century to also cover Key Question 6 from the 19th century (What caused the First World War?) so that learners have a background to the Treaty of Versailles and post-war developments.