for (var key in data) {
    if (key == 'Home'){
        $(".navDD").html(data[key]['text']);
    }
}

for (var key in data) {
    if (key == 'Home'){
        $(".navDD").html(data[key]['text']);
    }
}

you should also make sure that you are working with an object when using for loops. That might be where your 'undefined' error is coming from.

if (typeof data === 'object'){
    for (var key in data) {
        if (key == 'Home'){
            $(".navDD").html(data[key]['text']);
        }
    }
}