Answer:
B, A or D
Explanation:
Examples of secondary sources include: journal articles that comment on or analyse research. textbooks. dictionaries and encyclopaedias.
C. Archaeology is your answer
Answer:
It stretched from the Baltic Sea in the north to the Black Sea in the south, involved most of Eastern Europe, and stretched deep into Central Europe as well. The term contrasts with "Western Front", which was being fought in Belgium and France.
Explanation: