Adding Math Random to Scrolling Images

Hi, newbie here. Can someone please help me with sample code to add randomness to my scrolling images? The goal is for the user to click the mentioned color. I need random colors to scroll. Here is the code: Help please : )
background = display.newImage( “nightstars.png” )

pinkball = display.newImage( “pink.png” )

pinkball.x = display.stageWidth/ 2
pinkball.y = display.stageHeight/ 1

pinkball.xScale = .5
pinkball.yScale = .5

local function scroll()
pinkball.y = pinkball.y -5;
if(pinkball.y <= -1100) then
pinkball.y = 1100;
end
pinkball.y = pinkball.y -1;
if(pinkball.y <= -1100) then
pinkball.y = 1100;
end
end

local options = { “blue.png”, “green.png”, “yellow.png”, “red.png” }

function showball ()
local mr = math.random( 1, 4 )
end

Runtime:addEventListener(“enterFrame”, scroll);

yellowball = display.newImage( “yellow.png” )

yellowball.x = display.stageWidth/ 2
yellowball.y = display.stageHeight/ 1.4

yellowball.xScale = .5
yellowball.yScale = .5

local function scroll()
yellowball.y = yellowball.y -5;
if(yellowball.y <= -1100) then
yellowball.y = 1100;
end
yellowball.y = yellowball.y -1;
if(yellowball.y <= -1100) then
yellowball.y = 1100;
end
end

Runtime:addEventListener(“enterFrame”, scroll);

greenball = display.newImage( “green.png” )

greenball.x = display.stageWidth/ 2
greenball.y = display.stageHeight/ 2.3
greenball.xScale = .5
greenball.yScale = .5

local function scroll()
greenball.y = greenball.y -5;
if(greenball.y <= -1100) then
greenball.y = 1100;
end
greenball.y = greenball.y -1;
if(greenball.y <= -1100) then
greenball.y = 1100;
end
end

Runtime:addEventListener(“enterFrame”, scroll);

blueball = display.newImage( “blue.png” )

blueball.x = display.stageWidth/ 2
blueball.y = display.stageHeight/ 6.1
blueball.xScale = .5
blueball.yScale = .5

local function scroll()
blueball.y = blueball.y -5;
if(blueball.y <= -1100) then
blueball.y = 1100;
end
blueball.y = blueball.y -1;
if(blueball.y <= -1100) then
blueball.y = 1100;
end
end

Runtime:addEventListener(“enterFrame”, scroll);

redball = display.newImage( “red.png” )

redball.x = display.stageWidth/ 2
redball.y = display.stageHeight/ -1
redball.xScale = .5
redball.yScale = .5

local function scroll()
redball.y = redball.y -5;
if(redball.y <= -1100) then
redball.y = 1100;
end
redball.y = redball.y -1;
if(redball.y <= -1100) then
redball.y = 1100;
end
end

Runtime:addEventListener(“enterFrame”, scroll);

orangeball = display.newImage( “orange.png” )

orangeball.x = display.stageWidth/ 2
orangeball.y = display.stageHeight/ -1.5
orangeball.xScale = .5
orangeball.yScale = .5

local function scroll()
orangeball.y = orangeball.y -5;
if(orangeball.y <= -1100) then
orangeball.y = 1100;
end
orangeball.y = orangeball.y -1;
if(orangeball.y <= -1100) then
orangeball.y = 1100;
end
end

Runtime:addEventListener(“enterFrame”, scroll);

[import]uid: 133869 topic_id: 25933 reply_id: 325933[/import]