What is wrong with the code fragment:

$.$ORIG x$3000$

AND R$0,$R$0,$ #$0$

AND R$2,$R$2,$ #$0$

ADD R$2,$R$2,$ #$7$

JSR SUB

ADD R$2,$R$2,$ ASCII

ADD R$0,$R$2,$#$0$

TRAP x$21$

SUB ADD R$2,$R$2,$#$9$

ADD R$7,$R$7,$#$1$

RET

ASCII $.$FILL x$0030$

$.$END

Group of answer choices

Nothing is wrong, the program outputs $16$

We are modifying the contents of register R$7.$ This destroys the linkage back to the calling program.

TRAP x$21$ will not work after a subroutine call.

We are adding the x$0030($ascii code for $0),$ which is unnecessary.