The plant belongs to the group Angiosperm. Vascular plants with seeds could be cycads, Gingko, conifers, or angiosperms. Among those groups, only angiosperms have flowers.
The plant they found have colored, scented flowers which suggests that it could be pollinated by insects or birds. Colored flowers attract birds and insects. Color serves as a guiding mark. Talking of scent, it does not attract bird, but attracts insects. It also serves as the guiding mark.
Both. You can use it as singular or plural.
The theory of continental drift was given a scientific status during the:
1960's.