For this case we can translate the sentence given as:
I have achieved what I want with the _________ of my forehead.
The options given are:
Sweat
Thorough
Pattern
Proficient
In Spanish it is very common to relate hard work to the sweat of the forehead. That is, the phrase "With the sweat of my forehead" is related to a strong job that always allows us to obtain satisfactory results.
Thus, the correct option is option A. (Sweat)
I got what I want with the sweat on my forehead.
Answer:
He conseguido lo que quiero con el sudor de mi frente.