Answer: option C) cowpox and smallpox are caused by the same virus
Explanation:
Cowpox is a skin disease that affects cattle. It is caused by an Orthopoxvirus, with lesions occurring principally on the udder and teats of the animals.
Human infection may occur from touching infected cows, and thus giving immunity to smallpox (an acute infection caused by the same poxyvirus, in HUMANS)
So, Jenner's successful use was because cowpox and smallpox are caused by the same virus
Answer: D. the mucus that helps the sperm travel to the uterus is too thick.
Artificial insemination is the technique in which the sperms are introduced into the female's cervix or uterine cavity. This results in pregnancy through in vivo fertilization. Women cervix is blocked by thick mucus which block the entry of sperms. Therefore, artificial insemination would be better in such situation than other forms of treatment.
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