Select one option that shows the line number where assignment is first used in the algorithm in Figure 1.
Figure 1
1 OUTPUT "Enter your marks:"
2 score ← USERINPUT
3 IF score > 80 THEN
4 grade ← "A"
5 ELSE
6 grade ← "B"
7 ENDIF
Line 1
Line 2
Line 3
Line 4