It's asking what's true, so let me break this down for you.
If you look at the table, y has a row under the x row. Each of the boxes have numbers, and it's a so-called "pattern graph." A says, "The value of the function at x = 0 is y = 3." That means that the number 0 in the "x-row" has a 3 in the "y-row" (or below that number. That's all there is to it, and you just repeat this except different numbers, however... C and D aren't horizontal from each other so they are incorrect.
A. 10 boys to 12 girls because both numbers in the given ratio have been multiplied by two 5*2=10 6*2=12. None of the other options can be simplified to the original given ratio of 5:6.