Answer:
Sediment in rivers gets deposited as the river slows down. Larger, heavier particles like pebbles and sand are deposited first, whilst the lighter silt and clay only settle if the water is almost still.
B. Histones is the correct answer.
Lifespan - could be due to predators and food intake
The deep sea vent organisms or benthic organisms normally live in dark conditions because of no penetration of sunlight. These organisms in order to colonize ocean surface must develop photo sensory receptors and should adapt to the light conditions along with variation in temperatures and pressure in ocean currents.