16. Which of the following is essential for the production of thyroxine that changes a tadpole to a frog?

(a) Sodium (b) Iodine (c) Nitrogen (d) Oxygen                                                            (    )

 

(b) iodine

(b) Iodine. Iodine is essential for the production of thyroxine that changes a tadpole to a frog. If a lake, river or any other water body in which tadpole lives does not contain iodine that tadpole will not change in an adult frog. 

Iodine (c) hope it helped! :)

Iodine

Iodine because it is jaat answer so it is never wrong