Answer:
First we can cancel out B.
If anything you SHOULD NOT dive in shallow areas unless you are a trained professional.
Which means Canceling out D as well
Now you have A and C.
Not going to be C, as long as there are people around you incase you drown, and that they are there to help, you will be fine. You do not need a friend at all times.
And lastly A is your answer.
Never swim alone, you could drown, hit your head on something, slip and fall, and no one could help you.
Therefore, option A.
Hope this helps!
Have a nice day! :)))))))