Question 22 Which sentence best explains what the following production rule describes? ::= identifier | identifier, An is a single identifier or a comma-separated list of two or more identifiers. It's not a valid production rule. An is two identifiers with a comma between them. There's insufficient information to explain it. Question 23 It's not possible to construct a sequence of derivations from a parse tree. True False Question 24 While attempting a derivation in an attribue grammar, the value of a predicate function is false. What does this indicate? An unattributed parse tree cannot be constructed. There is semantic information that needs to be passed up the parse tree. The syntax or static semantics rules of the language have been violated. The grammar rule it is associated with is missing. Question 25 In a parse tree for a grammar, the leaves are always terminal symbols. True False Question 14 Consider the expression a-b-c. If the operator - has right associativity, this expression would be interpreted as: a-(b-c) (a - b)- (a-b-c) a syntax error