What happens to the local variable (with in a file) that is not used at all.

[SuperRookie]

Let's say I have to following code in a lua file

local varA
local varB = 0
local varC = "stringA"
 
local function funcA()
    local varD
    local varE = 1
    local varF = "stringB"
end

I know that varD to varF are removed from CPU when the funcA is terminated.

But, what happens to varA to varC and funcA?

Do they still stay in memory although they are not called or used, or collected by garbage collection at EOF?