Answer: The correct answer is Y chromosome.
Step-by-step explanation:
Fertilization is a process of fusion of male gamete with the female gamete to produce an offspring.
Female gametes are ova or egg and male gametes are sperms.
Female gametes carry a pair of chromosomes which are XX, while male gametes contain a pair of chromosome XY.
If Y chromosome fertilizes the egg, it will result in a male and if X chromosome fertilizes the egg, it will result in a female.
Hence, the correct answer is Y chromosome.