Final answer:
The Carters may claim three dependency exemptions on their joint tax return, likely for their daughter, Evan's grandmother, and their family friend Peggy, assuming they meet IRS requirements for dependents.
Step-by-step explanation:
The Carters may claim three dependency exemptions on their joint return for 2017. These exemptions could potentially include their daughter Pamela, who is a full-time student under the age of 24 and still qualifies as their dependent, Evan's grandmother Belinda, who they fully support, and Peggy, who is a friend of the family living with them and likely meets the requirements for a qualifying relative if they provide more than half of her support. However, it's important to note that some qualifications depend on specific tax laws applicable to the tax year in question and further details about the relationship and income of the dependents.