¿ ~Which one would YOU save?
You haven't taken the scenario fully into consideration. Say you decide to save the stranger. You swim over, grab the victim around the ribcage, and try to swim her to safety. You get to the edge of the pool and the woman accuses you of trying to cop a feel. You argue back that you're a woman and she accuses you of being a lesbian trying to cop a feel. Your friends all take your side, but secretly they're wondering if you really are a lesbian who likes to take advantage of drowning strangers. If you are a man, your friends don't have to wonder, they already know. You develop a cramp in your leg, a hysterical reaction to being told repeatedly from the time you were four that swimming right after you eat will cause you to get cramps. Your friends talk about you behind your back, you lose your job because the woman has slandered you, and you go home to bury your favorite pet before hanging yourself from the pecan tree in your backyard.
If the victim was a man, you'd pull him to safety, only to find that in your urgency to save this person's life, you've cracked his ribs. He sues you for an exhorbitant amount of money, so that Judge Joe Brown rules that your house will be put up for sale so that you can pay the damages. You cannot afford to bury your dead pet, and you can no longer sleep at night because the animal's dying shrieks still haunt you. Luckily, you are put out of your misery when you choke to death on a banana sandwich while laying suppine on Wilshire Blvd. in the cardboard box you now call home.
Say you choose to save your pet. You swim over to the poor panicked animal and in its desperation to save its own life, it claws your throat out and its own in the process. If your pet was a snake, you would let it die because snakes should never be thrown into water. At any rate, you, your pet, and the stranger would die, and there's nothing wrong with that because everyone would die eventually anyway. Maybe people would say you were noble, but most likely they would shut down the local public pool for the rest of the season, and all the neighborhood children would hate your guts and throw dog@#!!! at your grave marker.
My advice would be to simply leave the scene of a drowning-in-process as quickly as you possibly can. Go and have a root beer float and think how lucky it is that it isn't you in there drowning. You can always go out and buy a new pet, and you already have plenty of friends, so you'll lose nothing by a stranger's passing away. The only time to ignore this advice is if the drowning stranger is someone who's rich and/or famous, or if you are rich and/or famous and wish to generate good publicity by trying to save your pet. (If you are blonde, you can simply tell reporters that you did not notice the drowning stranger; if you are not blonde--bleach is pretty cheap. Buy some and use it. Unless you are olive complected, because that always looks strange. Some lightskinned African Americans can look quite fetching, however, with bleached blonde hair.)