In a family 19 people eat only vegetarian, 9 people eat only non veg., 12 people eat both veg and non veg.. How many people eat veg in the family?  Choose the most appropriate option:
A) 20 B) 31 C) 9 D) 31 E) 21

Rationale: "total people eat veg = only veg + both veg and non veg total = 19 + 12 = 31 answer = b"
Answer: B