The
total surface area of a regular pyramid
is the sum of the areas of its lateral faces and its base.
The area of the faces = four times the area of the triangle
= 4 * ( 0.5 * height * base )
= 4 * ( 0.5 * 16 * 19 ) = 608
The area of the base = area of a square
= 16 * 16 = 256
So, the total area = 608 + 256 = 864 units²
So, the correct answer is option A