Why are small drops of liquid spherical in shape?

(N/A) liquid-air interface possesses surface energy. For a given volume,the surface with the minimum energy is the one with the least surface area.
$A$ sphere possesses this property,as the surface area of a sphere is the minimum for a given volume.
Hence,if gravity and other external forces (such as air resistance) are negligible,liquid drops tend to be spherical to minimize their surface energy.
Furthermore,the cohesive forces between the liquid molecules are stronger than the adhesive forces between the liquid and air molecules,which helps the drop maintain its spherical shape.