Oxygen and carbon dioxide pass through the plasma membrane by passive diffusion facilitated diffusion active transport

The correct answer is option B, Diffusion

Explanation:

Carbon dioxide and oxygen diffuse across the semipermeable membrane due to the variation of concentration across the membrane (known as concentration gradient). Oxygen diffuses into the cell from outside because its concentration is high on the outer side of the cell wall. While carbon dioxide diffuses out of the cell, because its concentration is high on the inner side of cell membrane.  

Also, both carbon dioxide and oxygen are non polar and small sized molecules due to which they can be easily transported across the lipid membrane.  

Magnolia is a large genus of about 210 flowering plant species in the subfamily Magnolioideae of the family Magnoliaceae. It is named after French botanist Pierre Magnol. Magnolia is an ancient genus. Appearing before bees did, the flowers are theorized to have evolved to encourage pollination by beetles. To avoid damage from pollinating beetles, the carpels of Magnolia flowers are extremely tough. Fossilized specimens of M. acuminata have been found dating to 20 million years ago, and of plants identifiably belonging to the Magnoliaceae date to 95 million years ago. Another aspect of Magnolia considered to represent an ancestral state is that the flower bud is enclosed in a bract rather than in sepals; the perianth parts are undifferentiated and called tepals rather than distinct sepals and petals. Magnolia shares the tepal characteristic with several other flowering plants near the base of the flowering plant lineage such as Amborella and Nymphaea.

Explanation: