When ultraviolet rays from the sun reach the upper layers of the atmosphere, they sometimes react with oxygen gas. this starts a process that can eventually produce ozone. in what way is this process beneficial to human life

Ozone layer protects from excessive amount of UV rays coming from the sun

Explanation:

Oxygen is converted into ozone by the following net balanced equation which requires UV light for initiation:

The process is extremely vital for human life. Let's think about the atmosphere. Ozone layer is also known as a protective layer, since it protects people from harmful ultraviolet radiation that is coming from the sun.  In reality, we experience ultraviolet rays from the sun all the time, this is the reason why people get tanned (we wouldn't be able to achieve this with simply visible light). However, ozone layer controls the amount of the UV rays that reach Earth and decreases that number to the level where it becomes harmless to the people living on Earth.

particle   p is an electron and particle q is a neutron

it is the most commonly accepted one