Answer:
A and D have whole grid squares that are the same size and aren't over lapping
C has overlapping grid squares making it hard to count
B can't be used to find area because some of the grid squares are different sizes
You still could use B because four of the smaller squares seems to be equivalent to one of the larger squares
Step-by-step explanation:
Ah...Trigonometry is fun!
The law of sines states:

The transitive property (switching the orders of the equations) applies here. Therfore, we can say that

We then plug in our given values to find C


Solving, we get 0.8557316387.
We're not done yet!We are trying to find an angle measure, so we'll do the inverse of the ratio we used (sin).
arcsin0.8557316387 (arcsin is the same as inverse sin)
=
58.8 (approximate)
So the measure of angle C is 58.8. You could check this by reinserting it into the equation

.
:)