Diagram 4 best illustrate an event in reproduction that would most directly lead to the formation of a human embryo.
How human embryo formation occurs?
During fertilization, the sperm and egg unite in one of the fallopian tube of female reproductive system to form zygote.
Then zygote goes through some stages of embryogenesis in order tp reach implantation step.
Here in the diagram 4 sperm and egg are shown to get unite and formation of zygote can take place which eventually lead to embryo formation.
To know more about embryogenesis :
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