Consider the given grammar G:
S→F∣HF→p∣cH→d∣c
Ambiguity Analysis:
For the terminal string c, there are two distinct leftmost derivations:
S⇒F⇒c
S⇒H⇒c
Since the string c has two distinct parse trees (and two distinct leftmost/rightmost derivations), the grammar G is ambiguous.
Parsing with LL(1) and LR(1):
No ambiguous grammar can be LL(1) because there will be multiple entries in the LL(1) parsing table (FIRST/FIRST conflict: FIRST(F)∩FIRST(H)={c}). Thus, an LL(1) parser cannot deterministically parse all strings generated by G.
Similarly, no ambiguous grammar can be LR(1) (or LR(k) for any k) because it leads to reduce/reduce conflicts in the LR state representing the reductions F→c and H→c. Thus, an LR(1) parser cannot parse all strings generated by G.
Hence, neither S1 nor S2 is correct (Option D).