Answer:
B) restores the diploid number of chromosomes.
Explanation:
A pronuclei is the nucleus of a male (sperm) or female (egg cell) reproductive cell during fertilization (fusion of gametes). These pronuclei possess the genetic material that will eventually fuse when their membranes dissolve, their chromosomes then combine and become an embryo with a diploid nucleus that will contain a full set of chromosomes (23+23=46 chromosomes.)
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