I NEED HELP ASAP! Correct answer will be marked BRAINLIEST

1. A function of the female reproductive system is to provide a nourishing environment in which a fertilized can develop into an embryo.

A. ovary
B. sperm
C. egg
D. uterus

2. A couple enters the doctor’s office and expresses concern that they are having difficulties becoming pregnant. The doctor may find that one or both individuals are suffering from

A. an ovarian cyst.
B. testicular cancer.
C. endometriosis.
D. infertility.

3. You can perform at home which can help to detect reproductive problems early and allow you to seek the appropriate medical attention.

A. self-exams
B. exercise
C. sexual activity
D. ovulation

[120 total points] (public health) in one of the largest human experiments ever conducted, in 1954 a randomized controlled trial was run to see whether a vaccine developed by a doctor named jonas salk was effective in preventing paralytic polio. a total of 401,974 children (ages 6–9), chosen to be representative of those who might be susceptible to the disease, were randomized to two groups: 200,745 children (the control group c) were injected with a harmless saline solution (a placebo) and the other 201,229 children (the treatment group t) were injected with salk’s vaccine. what was the point of giving saline solution to the children who didn’t get the vaccine? explain briefly.