How do i reference a functions outcome if its a string?

Hello, Im trying to spawn in a certain part at a certain location using the string of a random rarity generator i made. I just cant seem to figure out how to reference the string as a Boolean value.

local Spawner = script.Parent
local ServerStorage = game:GetService("ServerStorage")
local AridPlants = ServerStorage:FindFirstChild("AridPlants")

local Rarity = {
				{"Common",40},
				{"UnCommon",35},
				{"Rare",20},
				{"Legendary",4},
				{"Mythic",1}
}
local TotalWeight = 0

for _,ItemData in pairs(Rarity) do
	TotalWeight = TotalWeight + ItemData[2]
end

local function chooseRandomRarity()
	local chance = math.random(1,TotalWeight)
	local counter = 0
	for _,ItemData in pairs(Rarity) do
		counter = counter + ItemData[2]
		if chance <= counter then
			return ItemData[1]
		end
	end
end
	while true do
		Spawner.ClickDetector.MouseClick:Wait()
			print(chooseRandomRarity())
	end
	
		if chooseRandomRarity() == "Common" then
			local c = AridPlants:FindFirstChild("1")
			c.Parent = game.Workspace.PlantSpawner
			c:MoveTo(Spawner.Position)
			print("Spawned")
			
		end