Respuesta :
Only one of them does not contain a colloquialism, so the answer is C (although, using the helping verb "is" makes it undesirable). "Being on cloud nine," "being over the moon," "walking on air," these are all informal sayings. Process of elimination will likely help you answer the rest of these.
The given sentence can be rewritten using formal language in the following way: C) Nancy is overjoyed.
What is formal language?
Formal language actually refers to the use of words that doesn't show familiarity. Formal language eliminates the use of slangs and some stylish words which depicts familiarity.
Thus, "Nancy is overjoyed" is actually formal unlike the other options.
Learn more about formal language on https://brainly.com/question/2285346
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