In ovules of Angiosperms, which one of the following is not a haploid cell?

In angiosperms, the ovule contains both sporophytic (diploid) and gametophytic (haploid) tissues. The nucellus is the central part of the ovule that encloses the embryo sac and is composed of diploid (2n) maternal sporophytic tissue [2]. In contrast, the female gametophyte (embryo sac) develops from a haploid megaspore through mitosis [1]. This process results in several haploid (n) cell types: the egg cell, which is the female gamete; two synergids that flank the egg; and three antipodal cells located at the chalazal end [1]. While the synergids, egg, and antipodals are all components of the haploid gametophyte generation, the nucellus remains part of the diploid sporophyte generation [2]. Therefore, the nucellus is the only cell type among the options that is not haploid.

Sources

1. [2] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/megagametogenesis
2. [1] https://pmc.ncbi.nlm.nih.gov/articles/PMC3268550/