To determine which two elements in the list would bond together based on their ionic charges, we can look at the groups and common ionic charges of the elements:
- Potassium (K) is in Group IA and has a charge of +1 when it forms an ion (K⁺).
- Calcium (Ca) is in Group IIA and has a charge of +2 when it forms an ion (Ca²⁺).
- Iodine (I) is in Group VIIA and has a charge of -1 when it forms an ion (I⁻).
- Neon (Ne) is in Group VIIIA and is a noble gas that typically does not form ions.
Based on these charges, potassium (+1) would bond with iodine (-1) to form potassium iodide (KI).
Therefore, the correct response is: potassium and iodine.