Among the elements , `Li, K, Ca, Cl` and `Kr`, the element `K` has the lowest `IE` and `Kr` has the highest `IE`.

Explanation

To determine whether the statement "Among the elements Li, K, Ca, Cl, and Kr, the element K has the lowest ionization energy (IE) and Kr has the highest IE" is true or false, we can analyze the ionization energies of these elements based on their positions in the periodic table.

### Step-by-Step Solution:

1. **Understanding Ionization Energy (IE)**:
- Ionization energy is the energy required to remove the outermost electron from a neutral gaseous atom.
- Generally, ionization energy increases across a period (from left to right) and decreases down a group (from top to bottom).

2. **Identifying the Elements**:
- The elements in question are Lithium (Li), Potassium (K), Calcium (Ca), Chlorine (Cl), and Krypton (Kr).
- Li and K are in Group 1 (alkali metals), Ca is in Group 2 (alkaline earth metal), Cl is in Group 17 (halogens), and Kr is in Group 18 (noble gases).

3. **Position in the Periodic Table**:
- Lithium (Li) is in Period 2.
- Potassium (K) is in Period 4.
- Calcium (Ca) is in Period 4 as well.
- Chlorine (Cl) is in Period 3.
- Krypton (Kr) is in Period 4.

4. **Comparing Ionization Energies**:
- **Potassium (K)**: Being in Group 1 and Period 4, it has a larger atomic size compared to Li and therefore has the lowest ionization energy among the listed elements.
- **Krypton (Kr)**: As a noble gas in Group 18, it has a complete outer electron shell, making it very stable and requiring a large amount of energy to remove an electron. Thus, it has the highest ionization energy.

5. **Conclusion**:
- Based on the above analysis, it is correct to state that Potassium (K) has the lowest ionization energy and Krypton (Kr) has the highest ionization energy among the given elements.

### Final Answer:
The statement is **True**.