Why should always be included in an example of formal writing ?
a. personal signatures
b. greetings or salutations
c. correct grammar
d. multiple paragraphs

A feature that should always be included in an example of formal writing is the following one:

C. Correct grammar.

Explanation:

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.

answer: the tobacco industry has traditionally been one of the most important industries in north carolina and a backbone of the state's agricultural heritage. yet as the north carolina economy continues to transition from an agricultural economy to a manufacturing and, increasingly, service-based economy, the industry faces new challenges, both at home and abroad

explanation:

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