function showonlyone(thechosenone) {
var nextcat = document.getElementsByTagName("div");
for(var x=0; x<nextcat.length; x++) {
name = nextcat[x].getAttribute("name");
if (name == 'nextcat') {
if (nextcat[x].id == thechosenone) {
nextcat[x].style.display = 'block';
}
else {
nextcat[x].style.display = 'none';
}
}
}
}