Answer:
The correct answer is male (+) haploid cell and female (-) haploid cell fuse to form a diploid zygote during sexual reproduction.
Explanation:
Sexual reproduction is the process that involves two processes- first is meiosis, involves the division of the number of chromosomes to half, and fertilization, the process of the fusion of two gametes or haploid cells and the maintaining or restoring of the original number of chromosomes.
In sexual reproduction, the specialized haploid cells or gametes from two different individuals, termed as the (+) and (−) mating types, join to form a diploid zygote.
thus, the correct answer is male (+) haploid cell and female (-) haploid cell.