The correct answer to this open question is the following.
Although there are no options attached we can say the following.
The role of lead King Birendra for the establishment of the SAARC was so important because he became the promoter of this economic association between the South Asian countries. King Birendra was a visionary that tried to be one step ahead and proposed the advantages of having a strong trade block.
King Birendra (1945-2001) became the King of Nepal in 1972. Although he was a king, he supported democratic ideas and tries to instill some in Nepal. Many historians and journalists believe that his role was determinant in the creation of SAARC, the South Asian Association for Regional Cooperation, formed by Nepal, Afghanistan, India, Buthan, Bangladesh, the Maldives, Pakistan, and Sri Lanka.