Thoughts on this code? Any tips for improvement?

var score = 0;

var question1 = prompt("Hello, Welcome to the Quiz App! Question One: What is the lowest point on Earth?");
if (question1.toUpperCase() === "MARIANA TRENCH") {
    score ++
}

var question2 = prompt("What country was invaded by Germany on September 1st 1939?");
if (question2.toUpperCase() === "POLAND") {
    score ++
}

var question3 = prompt("What city is the tallest skyscraper in the world located?");
if (question3.toUpperCase() === "DUBAI") {
    score ++
}

var question4 = prompt("What is the main language spoken in South Africa?");
if (question4.toUpperCase() === "ENGLISH"){
    score ++
}

var question5 = prompt("What continent is Malta located in?");
if (question5.toUpperCase() === "EUROPE"){
    score ++
}

alert("You scored " + score + " out of 5");

if (score === 5) {
    alert("You earned a gold crown!");
} else if (score === 3 || score === 4) {
    alert("You earned a silver crown!");
} else if (score === 2 || score === 1) {
    alert("You earned a bronze crown!");
} else {
    alert("You didn't earn a crown, try again next time!");
}