Answer: It would be D.
Explanation: they are synonyms
Answer:
In order to express oneself in a formal way, correct grammar must be used, since it makes for a serious tone, that is, it shows whatever was written was done so carefully and seriously, as a sign of respect for the addressee. In formal writing, even abbreviations must be avoided, as well as contractions. Therefore, correct grammar is the way to go if you want to achieve a formal tone.
This could be the death of a family member, or a certain academic/athletic achievement. Maybe the day you got a pet or the day that pet died. Maybe when you completed an important goal. If it's an important memory to you, you could use it.
Exclamation point because it's not formal or professional
