Option d is correct.. becoz.... Copper T when placed in uterus it realeses copper which make the uterus walls unfavorable for implantation it also hinders ovulation.. Hope It helps u...

Copper-T is a type of intrauterine device (IUD) that is commonly used as a form of contraception. It is a small, T-shaped device that is inserted into the uterus, where it releases copper ions that prevent pregnancy.

Prevents Implantation of Blastocyst:
- Copper-T works by creating a hostile environment for sperm, which makes it difficult for them to reach and fertilize an egg.
- Additionally, the copper ions released by the device also prevent the fertilized egg from implanting in the uterus, which effectively prevents pregnancy.

Prevents Ovulation:
- Unlike hormonal forms of contraception, Copper-T does not prevent ovulation.
- This means that women who use Copper-T continue to ovulate as normal, but the device makes it difficult for the sperm to reach the egg and fertilize it.

Prevents Fertilization:
- Copper-T primarily works by preventing fertilization, which is the union of the sperm and egg.
- The copper ions released by the device alter the structure of the sperm, making it difficult for them to swim and reach the egg.
- Additionally, the copper ions also affect the egg, making it less likely to be fertilized.

Both A and C:
- Because Copper-T prevents implantation of a fertilized egg and also prevents fertilization itself, the correct answer is option D - both A and C.
- Copper-T is a highly effective form of contraception, with a failure rate of less than 1%.
- However, it is important to note that Copper-T does not protect against sexually transmitted infections (STIs), so it is important to use condoms or other forms of protection if there is a risk of STI transmission.