Which of the following statements about food chain are correct?
(i) It includes repeated eating, i.e., each group eats the other and is subsequently eaten by some other group of organisms.
(ii) It shows a series of branching lines and bidirectional flow of energy.
(iii) It shows the unidirectional flow of energy and proceeds in a progressive straight line.
(iv) Omnivores occupy different trophic positions in different food chains.

Options

A. (i) and (ii) only
B. (i) and (iii) only
C. (ii) and (iv) only
D. (i),(iii) and (iv) only

Explanation

To determine which statements about the food chain are correct, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement (i)**: "It includes repeated eating, i.e., each group eats the other and is subsequently eaten by some other group of organisms."
- **Analysis**: This statement describes a characteristic of food webs rather than food chains. In a food chain, the relationship is linear where one organism is eaten by another, and it does not imply repeated eating among groups. Therefore, this statement is **incorrect**.

2. **Statement (ii)**: "It shows a series of branching lines and bidirectional flow of energy."
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