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Questão

Considere a seguinte gramática para expressões matemáticas simples: 

<expr> ::= <term> + <expr> | <term> - <expr> | <term> 

<term> ::= <factor> * <term> | <factor> / <term> | <factor> 

<factor> ::= <number> | (<expr>) 

<number> ::= [0-9]+ 

Qual das seguintes expressões é sintaticamente válida de acordo com essa gramática? 
A)

2 * (3 + 4)

B)

(2 * (3 + 4))

C)

2 * (3 + 4))

D)

2 * (3 + 4

E)

2 * 3 + 4

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