Final answer:
The appropriate initial action when a toddler is choking on a piece of food and appears slightly blue is to call for the emergency response team.
Step-by-step explanation:
The appropriate initial action when a toddler is choking on a piece of food and appears slightly blue is to D) Call for the emergency response team.
Choking can be a life-threatening emergency, and it's important to get professional help immediately. While it may be tempting to try other interventions like mouth to mouth resuscitation or giving water, it's best to leave the initial action to trained professionals who can provide the necessary assistance.