ans is c.bcoz metamorphosis is carried out By an harmone called thyroxine in tadpoles of frog.the harmone produced By thyroid gland that needs iodine.

Introduction:
When a tadpole larva is kept in iodine deficient pond water, it can have several effects on its development and metamorphosis. The absence of iodine, an essential micronutrient, can disrupt the normal growth and transformation process of the tadpole into a frog.

Effects of iodine deficiency:
When a tadpole larva is exposed to iodine-deficient pond water, the following outcomes can be observed:

1. Inhibition of metamorphosis:
- The most significant effect of iodine deficiency on tadpole development is the inhibition of metamorphosis.
- Metamorphosis is the process by which the tadpole undergoes a series of changes to transform into a frog.
- The absence of iodine interferes with the production of thyroid hormones, specifically thyroxine (T4), which are crucial for initiating and regulating metamorphosis.
- Without adequate levels of thyroid hormones, the tadpole's tissues and organs fail to undergo the necessary changes required for metamorphosis to occur.
- As a result, the tadpole remains in its larval form for an extended period, or may not undergo metamorphosis at all.

2. Development of miniature frog:
- In some cases, when tadpoles are kept in iodine-deficient pond water, they may still undergo metamorphosis, but the process is disrupted.
- The resulting frogs are often smaller in size compared to those that develop in iodine-sufficient environments.
- Iodine plays a crucial role in the growth and development of various tissues and organs, including the skeletal system.
- In its absence, the tadpole's growth is stunted, resulting in the development of miniature frogs.

Conclusion:
In summary, when a tadpole larva is kept in iodine-deficient pond water, it can lead to the inhibition of metamorphosis or the development of miniature frogs. Proper iodine levels are essential for the production of thyroid hormones, which regulate the transformation process. Without adequate iodine, the tadpole's growth and development are affected, resulting in abnormal or delayed metamorphosis.