Answer:
IUD, implant, injection
Step-by-step explanation:
According to the CDC, vaginal rings (like NuvaRing) lead to unintended pregnancy in 9% of women who report typical use within the first year of use and 0.3% of women who report perfect use.
Implants (like Implanon) lead to unintended pregnancy in 0.05% of women reporting both typical and perfect uses.
Contraceptive patches (like Evra patch) lead to unintended pregnancy in 9% of women reporting typical use and 0.3% of women with perfect use.
Intrauterine devices (IUDs, like ParaGard and Mirena) have an average of 0.5% rate of unintended pregnancy with typical use and 0.4% rate with perfect use.
The contraceptive injections (like Depo-Provera) have a 6% unintended pregnancy rate with typical use and a 0.2% for perfect use.
Finally, the contraceptive pill yields rates of 9% with typical use and 0.3% with perfect use.
So with perfect use, the most effective methods are implants first, then injections, and then IUDs.