What happens next in this paragraph?

How to train border collies
Break the trick down.
For instance, the command " stay " can be broken into a number of steps. The first step is to teach your dog to sit and not get up until you tell her to.
Select from: A. Then, you can move on to staying for a short time. Next, move on to staying for a longer period.. B. Then, then, push her hind legs to the bottom of your lap. As your dog sits, push her forward until you hear the word " stay " and encourage her on once she sits.. C. It's still important to train your border collies to always sit, as without sitting, they cannot obey. Teach your border collies to raise their legs high in the air.. D. Then, you gently let her down and tell her to get down again. You can try to motivate her by saying something like, " stay! Sit, sit! " you can also offer her a treat instead..
A.