The answer is 4 because Meiosis needs to be the first step to occur because meiosis produces gametes (egg and sperm), you can revisit all the phases of meiosis to learn that it will result in 4 non-identical haploid cells and then fertilization will take place, where the 2 haploid cells (egg and sperm) will be combined to make a diploid cell, which will produce a zygote
Egg(n) + sperm (n) = zygote (2n)
Hope that helps!
