Hazrat Muhammad (PBUH) wrote letters to kings in which year?

Prophet Muhammad (PBUH) began sending letters to various kings and rulers, inviting them to Islam, in the 6th year of Hijrah (6 AH). This pivotal initiative occurred shortly after the signing of the Treaty of Hudaybiyyah, which brought a temporary truce with the Makkans. This period of peace allowed the Prophet (PBUH) to expand the message of Islam beyond the immediate Arabian Peninsula.

• 5 AH (A) was the year of the Battle of the Trench (Khandaq), a defensive battle.
• 8 AH (C) was the year of the Conquest of Makkah, a major turning point.
• ان میں سے کوئی نہیں (D) is incorrect as 6 AH is the historically accurate year for this significant diplomatic outreach.