Hey there!
In order to solve this question, we want to isolate "t" on one side of the final equation using the original equation of

.
Let's start off by adding 4t to both sides of the equation. This will remove the "-4t" on the right side of the equation.
Now we have

.
Now, let's subtract both sides by G. This will move the "G" on the other side.

Now, let's fully isolate t by dividing both sides by 4. This will remove the coefficient for t.

Thus, your answer is C. Hope this helps! :)