easy
the equation of a line with vertex (h,k) is
y=a(x-h)²+k
given
vertex is (2,1)
y=a(x-2)²+1
we also know that (0,5) is on the line
x=0 and y=5 is a solution
5=a(0-2)²+1
5=a(-2)²+1
5=4a+1
minus 1 both sides
4=4a
divide 4
a=1
y=1(x-2)²+1 is the equation
or
y=(x-2)²+1
first option is answer
