Which of the following statements about crayfish is correct?

• A. Crayfish lack jointed appendages and have smooth limbs.
• B. Crayfish possess only a single, unsegmented limb on each side.
• C. Crayfish have jointed appendages, characteristic of arthropods.
• D. Crayfish have cilia instead of appendages for movement.

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the classification of crayfish. Crayfish are arthropods, which are characterized by having jointed appendages, segmented bodies, and an exoskeleton made of chitin.
2. Step 2: Analyze the first statement: 'Crayfish lack jointed appendages and have smooth limbs.' This is incorrect because crayfish, as arthropods, have jointed appendages, which are a defining feature of this group.
3. Step 3: Analyze the second statement: 'Crayfish possess only a single, unsegmented limb on each side.' This is also incorrect because crayfish have multiple jointed appendages, not a single unsegmented limb.
4. Step 4: Analyze the third statement: 'The correct answer is: Crayfish have jointed appendages, characteristic of arthropods.' This is correct because it aligns with the biological characteristics of arthropods, including crayfish.
5. Step 5: Analyze the fourth statement: 'Crayfish have cilia instead of appendages for movement.' This is incorrect because crayfish use their jointed appendages for movement, not cilia, which are typically found in other organisms like protozoa or certain epithelial cells.