I think the answer would be. B
<span>the portion of an antigen that binds covalently to an antibody</span>
Some spicules are formed of the mineralized substances calcium carbonate and silica, while others are made of an organic substance called spongin. Sponginskeletons<span> were and are used as scrubbers in bathtubs, though they are fairly expensive. The ubiquitous bathtub accessory called a lufa is NOT a </span>sponge<span>, but a plant.</span>
Answer: When a plant is exposed to light, photons of appropriate wavelength will strike and be absorbed by the pigment-protein complexes arrayed on the thylakoid membranes. When this happens, the energy of the photon is transferred to the pigment molecule, thus causing the pigment to go into an electronically excited state. :)
Explanation: