Which of the following assisted reproductive technology has been used for the longest time period?

(a) In vitro fertilization
(b) Artificial insemination
(c) Intracytoplasmic sperm injection
(d) Gamete intra fallopian transfer

Dear student 
Please find your answer below to the asked query 

Option b is correct. 
Artificial insemination AI is the assisted reproductive technology that has been used for the longest time period. 
It can help in treating certain kinds of infertility in both male and female. In this procedure, sperms are directly inserted in female cervix, fallopian tube or uterus. This helps sperm to reach quickly and thus bypassing any obstructions. 
Intra uterine insemination IUI is most common form of AI.

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