Answer:
two gametes come together and chromosomes combine is the correct answer
Explanation:
Fertilization occurs when the haploid gametes are fused to form a zygote.
In human The male sperm fuse with female egg to give rise to a diploid cell inside the women's body in the Fallopian tube.
The sperm and egg have a half number of the chromosome, and they are haploid they have chromosomes (single set), and when they fuse to form a zygote,chromosome combine and Zygote has two sets(23pairs) of the chromosomes.
Thus fertilization is a process which occur when two gametes come together and chromosomes combine.
