Let’s analyze the matching between the carnivorous plants and their modified organs:
- (P) Pitcher plant (Nepenthes): The pitcher plant modifies its leaf into a pitcher-shaped structure, which it uses to trap prey. Hence, the correct match for P is \( P-1 \).
- (Q) Bladderwort (Utricularia): Bladderworts have modified leaves in the form of small bladders that trap prey. Thus, the correct match for Q is \( Q-1 \).
- (R) Sundew (Drosera): Sundew plants have modified leaves covered in glandular hairs that secrete sticky substances to trap prey. Hence, the correct match for R is \( R-1 \).
- (S) Venus flytrap (Dionaea): The Venus flytrap modifies its leaf into a structure with hinged lobes that trap insects. Hence, the correct match for S is \( S-1 \).
Thus, the correct answer is (B).