The PRINCIPLE OF PROPORTIONALITY in International Humanitarian Law (Article 51(5)(b) AP I 1977):

1. AP I 1977 Article 51(5)(b) deems INDISCRIMINATE an attack which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be EXCESSIVE in relation to the concrete and direct military advantage anticipated. 2. The principle requires WEIGHING incidental civilian harm against military advantage. 3. NOT a 'no civilian casualty' rule, but a proportionality test. 4. Violation is a war crime under Article 8(2)(b)(iv) Rome Statute. 5. Hence option B is correct. _Source: International HR Treaties + Indian Constitutional Jurisprudence — Additional Protocol I 1977, Article 51(5)(b)_