What is the correct configuration stanza for a Xen virtual machine?

What is the correct configuration stanza for a Xen virtual machine?

A.
kernel "/boot/vmlinuz2.6.18.8xwnU";
ramdisk "/boot/initrd.img2.6.18.8xwnU";
memory "256";
name"Centos";
disk[‘phy:/dev/sdb1,xvda1,w’];
root"/dev/xvda1";

B.
kernel "/boot/vmlinuz2.6.18.8xwnU"
ramdisk "/boot/initrd.img2.6.18.8xwnU"
memory "256"
name"Centos"
disk[‘phy:/dev/sdb1,xvda1,w’]
root"/dev/xvda1"

C.
kernel = "/boot/vmlinuz2.6.18.8xwnU"
ramdisk = "/boot/initrd.img2.6.18.8xwnU"
memory = "256"
name= "Centos"
disk= [‘phy:/dev/sdb1,xvda1,w’]
root= "/dev/xvda1

D.
kernel [‘/boot/vmlinuz2.6.18.8xwnU’]
ramdisk [‘/boot/initrd.img2.6.18.8xwnU’]
memory [‘256’]
name[‘Centos’]
disk[‘phy:/dev/sdb1,xvda1,w’]
root[‘/dev/xvda1’]