It was observed that the tadpoles are not growing into adult frog in a village pond. A scientist who was asked to find the reason for this concluded that the pond water did not contain sufficient amount of a mineral P which could make a hormone Q. The hormone Q can cause a phenomenon R in tadpoles so that they from become adult frogs.
What are (i) P (ii)Q, and (iii) R ?

Explanation

To solve the question, we need to identify the mineral (P), the hormone (Q), and the phenomenon (R) related to the growth of tadpoles into adult frogs.

### Step-by-Step Solution:

1. **Identify the Mineral (P)**:
- The problem states that the pond water does not contain a sufficient amount of a mineral that is essential for the growth of tadpoles into adult frogs.
- The mineral that is crucial for the production of certain hormones in amphibians, including frogs, is **iodine**.

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