The correct sequence of events is : C,D,B,A.
Iron rich magma in the earth's core heats up because of radiation and the pressure exerted by the other layers of the earth. This heat in the crust trigger convection currents in the mantle. The magma closest to the core will be hotter and therefore less dense than other layers. Being less dense the layer will rise towards the crust, eventually becoming cooler and sinking back down in a circular motion.
The continued circular motion creates electric currents which then generates the magnetic field.
Photosynthesis. Oxygen<span> is a by-product of the photosynthetic </span>process<span>.</span><span> The light-dependent reactions use H 2 O and </span>produce<span> O 2.</span>
The correct answer is option C, that is, the presence of the nuclear membrane.
Cyanobacteria is a phylum of bacteria that attain their energy via the process of photosynthesis, and are the only photosynthetic prokaryotes possessing the tendency to generate oxygen. As a prokaryote, they are devoid of the nuclear membrane.
Euglena refers to a single cell flagellate eukaryote. It comes under the class Euglenoidea. The species of Euglena are witnessed in salt water and in freshwater. Being a eukaryote, they possess nuclear membrane.
The <u>Trachea</u> is a 5-inch long tube made of C-shaped hyaline cartilage rings lined with pseudostratified ciliated columnar epithelium.
Hope that helps!