Datastep Execution

data x;
set a;
length name $ 5;
retain name 'David';
do i=1 to 5;
initial = substr(name,1,1);
end;
if initial .ne. 'D' then delete;
run;

How many times is this data step executed based on the datasets below?

data a
--------
name age
Bob   35
Jason 57
John  79

data b
-------
name  age
Bob    2
Dawn  4

data c
-------
name   age
Dawn   30
Bob     35
Jill        40
Jason    45
deb       50


Pick the answer-
a) 2
b) 3
c) 5
d) 10

Check the comments below for answers....