I think that the answer is A.
Okay, this is not really an answer, but I think in 2020, we will be in the 20 trillions. O know that is not the answer you were looking for, but its all I got.
The minimum of a quadratic function, with a positive coefficient a, is its vertex.
Let's find the x₀ coordinate.

Now we need to find y₀ coordinate. That will be the minimum of function.

So, the minimum cost to produce the product is $13
Decompose 5x^2 − 70x + 258 into multipliers

Answer: 5(x − 7)^2 + 13; The minimum cost to produce the product is $13.