The parent function
f(x) = x²
opens up and has its vertex at (0, 0).
When it is reflected across the x-axis, it opens down and its equation becomes
g(x) = -f(x) = -x²
When the vertex is translated 1 unit to the left, to (-1, 0), the function becomes
g(x) = -f(x+1) = -(x+1)²
Your best choice is ...
y = -(x + 1)²
