give the formal or informal definition of the following words. choose the letter only

1.)Cyberbullying (formal)
a. an electronic posting of mean-spirited messages about a person often done anonymously

b. electronic posting of mean-spirited messages

2.)Strength (informal)
a. the quality or state of being physically strong

b. embodying or affording firmness

3.)bully (formal)
a.person who uses strength of influence to harm or intimidate those who weaker

b. those who always consider themselves superior to others

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