Backbiting (ghibah) is classified as a major sin in Islam. The Qur'an explicitly condemns it in Surah Al-Hujurat (49:12): "And do not backbite one another. Would one of you like to eat the flesh of his dead brother? You would detest it." This powerful metaphor compares backbiting to the repulsive act of consuming the flesh of one's deceased brother, emphasising how grave the sin is.
The Prophet Muhammad (peace be upon him) defined backbiting as "mentioning your brother in a way that he would dislike," even if what is said is true. If the statement is false, it becomes buhtan (slander), which is an even greater sin. Backbiting destroys social bonds, violates the honour of fellow Muslims, and erodes trust within the community.
The other options are incorrect. Backbiting is never recommended, regardless of circumstances. It is not classified as merely optional (implying neutrality), nor is it permissible during war. Islam maintains strict ethical conduct even in conflict, and backbiting remains prohibited under all conditions. Scholars list it among the kaba'ir (major sins) that require sincere repentance and, where possible, seeking forgiveness from the person who was wronged.