Solution

The correct answer is B and C Only

Key Points

A context-free grammar (CFG) is considered ambiguous if there exists a string in the language generated by the grammar that has more than one derivation tree, meaning it can have multiple Leftmost Derivation Trees (LMDTs) or Rightmost Derivation Trees (RMDTs). 

Definition:
A CFG G = (V, T, P, S) is said to be ambiguous if and only if there is a string in T* that can be derived in more than one way, resulting in more than one parse tree.

• - V is a finite set of variables (non-terminal symbols).
• - T is a finite set of terminals (terminal symbols).
• - P is a finite set of productions of the form \(A \rightarrow \alpha\) , where A is a variable and \alpha is a string of symbols from the set  \((V \cup T)\)*.
• - S is the designated start symbol from the set of variables.