My script

function choose {

echo " What does NLX stand for"

local default="$1"
local prompt="$2"
local choice_yes="$3"
local choice_no="$4"
local answer

read -p prompt answer
[ -z "$answer" ] && answer="$default"

case "$answer" in
[yY1] ) eval "$choice_yes"
        #error check
        ;;
[nNo] eval "choice_no"
        #error check
        ;;
*    ) printf "%b" "Unexpected Answer '$answer'" >&2 ;;
esac

}