How do you write "Hello World" in an alert box?

$\{$$a$->$questionintifier$\}$ Yan$$t

a$.$

alert$("$Hello World"$)$;

b$.$

msg$("$Hello World"$)$;

c$.$

alertBox$("$Hello World"$)$;

d$.$

msgBox$("$Hello World"$)$;