In order to prevent the possibility of venous stasis, a nurse is educating a surgical client on how to perform leg exercises. Which statement by the client indicates a sound understanding of leg exercises?

"I'll make sure to do these, as long as my doctor doesn't tell me to stay on bed rest after my operation."

"I'll try to do these lying on my stomach so that I can bend my knees more fully."

"I'll practice these now and try to start them as soon as I can after my surgery."

"I'm pretty sure my stomach muscles are strong enough to lift both of my legs off the bed at the same time."