Consider the JavaScript code segment below:

var a;

for

$($

var

i

$=$

$0$

;

i

$<$

$20$

;

i

$+$

$+$

$$Math$.$floor

$($

Math

$.$

random

$()*100$

$+$

$1$

;

if

document.write

$($

a

$+$

$"")$

;

$\}$

$\}$

Which of the following is a possible output of this code segment?