Go through the following statements.
(i) In proteins, right handed and left handed helices are observed
(ii) In B-DNA, at each step of ascent, the strand turns `36^(@)`.
(iii) Living process is a steady - state in equilibrium.
(iv) The rate of reaction doubles or decreas- es by half for every `10^(@)` C change in ei- ther direction.
Find out the correct statement ?

Options

A. (i), (iii) & (iv)
B. (ii) & (iv)
C. (i) & (iv)
D. All are correct

Explanation

To determine the correct statements from the given options, we will analyze each statement one by one.

### Step 1: Analyze Statement (i)
**Statement (i):** In proteins, right-handed and left-handed helices are observed.

- **Analysis:** In proteins, the predominant structure is the right-handed alpha helix. Left-handed helices are rare and not commonly found in natural proteins. Therefore, this statement is **incorrect**.

### Step 2: Analyze Statement (ii)
**Statement (ii):** In B-DNA, at each step of ascent, the strand turns `36°`.

- **Analysis:** B-DNA is a double helix structure where the helix makes a complete turn every 10 base pairs, which corresponds to a rotation of `36°` per base pair. Thus, this statement is **correct**.

### Step 3: Analyze Statement (iii)
**Statement (iii):** Living processes are a steady-state in equilibrium.

- **Analysis:** Living systems maintain a non-equilibrium steady state. They are constantly exchanging materials and energy with their environment, which prevents them from reaching equilibrium. Therefore, this statement is **incorrect**.

### Step 4: Analyze Statement (iv)
**Statement (iv):** The rate of reaction doubles or decreases by half for every `10°C` change in either direction.

- **Analysis:** This statement is based on the general rule known as the Q10 rule, which states that for many biochemical reactions, the rate of reaction approximately doubles for every `10°C` increase in temperature. Therefore, this statement is **correct**.

### Conclusion
From the analysis:
- Statement (i) is incorrect.
- Statement (ii) is correct.
- Statement (iii) is incorrect.
- Statement (iv) is correct.

Thus, the correct statements are (ii) and (iv). The answer is option **B: 2 & 4**.