ITPEC FE Subject B April 2024 Question 1

Fill in blanks for a grade-classification function using if/elseif/else.

The table maps scores to letter grades: 80–100 → "D", 50–79 → "P", 0–49 → "F". The function checks from highest range down:

1. if (score ≥ 80) → return "D" — covers 80–100
2. elseif (score ≥ 50) → return "P" — since the first check failed, score is already < 80, so this covers 50–79
3. else → return "F" — everything below 50

Blank A = ≥ (greater than or equal), because score 80 must be included in the "D" range.
Blank B = "P" (Pass), for scores 50–79.
Blank C = "F" (Fail), for scores 0–49.

Why not others:
- (a) = operator — equality check (score = 80) would only match exactly 80, not a range
- (b) = operator — same problem as (a), plus B and C are swapped
- (c) > operator with B="P", C="F" — score > 80 excludes 80 itself, which should get "D"
- (d) > operator with B="F", C="P" — wrong operator AND swapped grades
- (f) ≥ operator but B="F", C="P" — correct operator, but grades are swapped: 50–79 would get "F" instead of "P"

Key rule: In chained if/elseif, each branch inherits the negation of all previous conditions — so elseif (score ≥ 50) implicitly means score < 80 AND score ≥ 50.

AI-generated — may contain errors