An-Naazi'aat • EN-AL-JALALAYN
﴿ فَأَرَىٰهُ ٱلْءَايَةَ ٱلْكُبْرَىٰ ﴾
“And thereupon he [went to Pharaoh and] made him aware of the great wonder [of God's grace].”
So he showed him the greatest sign from among His nine signs namely the glowing hand or the slithering staff.