Your backyard is fenced in.  Your 3-year-old loves to play outside.  You have a lot to do inside.  Do you let your child play outside alone?

a.  You must be joking.
b.  No!  She is too young to be unsupervised even for a moment.
c.  Only if I can keep an eye on her through the window.
d.  Yes, if she has other children with her.
e.  None of the above.

Child-proofing. Safety. Supervision.