Answer:
A sounds like it fits the best
"The flight was postponed by bad weather for which I had a ticket". The sentence should read, "The flight for which I had a ticket was postponed by bad weather."
I think it would be a. formal
Three main languages were in use in England in the later medieval period – Middle English, Anglo-Norman (or French) and Latin. Authors made choices about which one to use, and often used more than one language in the same document.
Explanation: