The following observation are given for four metals :
(I) Metal H does not react with dilute HCI.
(II) Metal K reacts with warm water.
(III) Metal L does not react with water but displaces metal H from its aqueous salt solution.
(IV) Metal M reacts with cold water.
Choose the correct decreasing order of reactivity of the metals amongst among the following :

Options

A. `M gt L gt H gt K`
B. `K gt M gt H gt L`
C. `M gt K gt L gt H`0
D. `L gt H gt K gt M`

Explanation

To determine the correct decreasing order of reactivity of the metals H, K, L, and M based on the given observations, we can analyze the information step by step.

### Step-by-Step Solution:

1. **Analyzing Metal H**:
- Metal H does not react with dilute HCl.
- This indicates that Metal H has very low reactivity since it does not react with an acid.

2. **Analyzing Metal K**:
- Metal K reacts with warm water.
- This suggests that Metal K has a moderate level of reactivity, higher than Metal H.

3. **Analyzing Metal L**:
- Metal L does not react with water but displaces Metal H from its aqueous salt solution.
- Since Metal L can displace Metal H, it must be more reactive than Metal H. However, since it does not react with water, it is less reactive than Metal K (which reacts with warm water).

4. **Analyzing Metal M**:
- Metal M reacts with cold water.
- This indicates that Metal M is more reactive than both Metal K and Metal L, as it can react with water at a lower temperature.

### Conclusion:
Based on the analysis:
- Metal M is the most reactive.
- Metal K is next, as it reacts with warm water.
- Metal L is more reactive than Metal H but less reactive than Metal K.
- Metal H is the least reactive.

Thus, the correct decreasing order of reactivity is:
**M > K > L > H**