Metamorphosis is a biological process that involves

Step 1: Analyze the question The question asks what metamorphosis involves, so we need the option that best defines it.

Step 2: Explain the concept Metamorphosis is a biological process in which an organism undergoes a distinct change in body form and structure after birth or hatching, as it passes through different stages of its life cycle.

• Complete metamorphosis (holometabolous): egg → larva → pupa → adult. Examples are the housefly, butterfly, mosquito and beetle. Here the larva looks completely different from the adult.
• Incomplete metamorphosis (hemimetabolous): egg → nymph → adult. Examples are the grasshopper, cockroach and termite. Here the nymph resembles a small adult.
• Amphibians such as frogs also metamorphose: egg → tadpole → froglet → adult frog.

Step 3: Evaluate each option

• A. Growth and development from a zygote to an adult. This describes general growth and development, not metamorphosis specifically. Many organisms, such as humans, grow from a zygote to an adult without metamorphosis. ❌
• B. The change in form and structure during the life cycle of certain organisms. This matches the definition. It also says "certain organisms," which is correct because only some organisms metamorphose. ✅
• C. Regeneration of lost body parts. This is regeneration, as seen in lizards' tails and starfish arms. ❌
• D. Transformation from adult to larval stage. This is backwards, because metamorphosis goes from larva to adult. ❌

Step 4: Answer The correct option is B.

💡 Exam tip: Think of metamorphosis as "meta" = change and "morph" = form, so it means a change of form. If an option mentions a change in body form across life stages, such as larva to adult, that is your answer. Watch out for options that reverse the order, like option D.