Option A — Petals and Sepals
Petals attract insects through bright colours and fragrance, while sepals provide protection. Both help in pollination by attracting pollinators.
Source: Sexual Reproduction in Flowering Plants, Chapter 7
The textbook directly asks "What possible functions could the petals and sepals serve?" implying both attract insects/pollinators. Examiners expect you to identify both petals and sepals — not petals alone. Anther and stigma are reproductive parts, not attractants.