Official Solution:Wilhelm I was recognized by the Treaty of Frankfurt as the Emperor in 1871, when Germany first became a single, unified state.A. Wilhelm I was recognized by the Treaty of Frankfurt as the Emperor in 1871, when Germany first became a single, unified state.
B. Wilhelm I was recognized by the Treaty of Frankfurt in 1871 as Emperor, when Germany first became a single, unified state.
C. Germany first became a single, unified state in 1871, when the Emperor Wilhelm I was recognized by the Treaty of Frankfurt.
D. Germany first became a single unified state in 1871, when the Treaty of Frankfurt recognized Wilhelm I as Emperor.
E. In 1871, Germany first became a single, unified state, when the Treaty of Frankfurt recognized Wilhelm I as the Emperor of the country.
A. A is wrong not because it conveys a wrong meaning, but because it may be interpreted in two different ways and is hence ambiguous:
1. The recognition happened in 1871.
2. Wilhelm was recognised as emperor only for the year 1871.
B. Wrong position of dependent clause modifier "when Germany...."- should ideally touch "1871".
C. Problematic meaning: This option conveys that Wilhelm was already an emperor when the treaty recognized him. It is not clear the treaty recognized him as what.
D. CORRECT. E. Wrong position of dependent clause modifier "when Germany...."- should ideally touch "1871".
Answer: D