Helium decays to form lithium.

6

2

He →

6

3

Li +

0

-1

e

This type of nuclear decay is called.

its B on edge

Natural nuclear disintegration.

Explanation:

This is because it cannot be managed, like it needs no energy particle yo occur, so its natural for helium to decay.

But it is nuclear because helium decays to release an energy particle (Beta particle).