We can eliminate the first and the last option because the line is going upwards, not downwards(it would if it was negative or had the negative sign in front). We can cross out the second option because if it was 2^x+3, then it would be crossing (0,4) on the y-axis. Therefore the correct option is C, since it crosses right at (0,3).
Divide 12 by 3 and you'll get 4. That means 1/4 or a quarter of the 12 is 3. (Convert the fraction to its percentage form) 1/4 or 1 divided by 4 equals 0.25 Multiply 0.25 by 100 and you'll get 25%