Mesozoic era is a geological era lasting about 252 to 66 million years ago. During this era, gymnosperms were present as dominant vegetation and dinosaurs were present as dominant land vertebrates.
The first angiosperm (flowering plant) was evolved in Mesozoic era and by the end of Mesozoic era, flowering plants dominated in many regions, although other lower plants, such as ferns were also present in large number.
Thus, the correct answer is option). 'the first flowering plants appeared in the Mesozoic era, not the Paleozoic era.'
