The correct answer is option A, that is, placer deposits.
The concentration of heavy deposits known as the placer deposits are produced by the gravitational action, generally found in streams. The minerals that take place as placer deposits comprise copper, gold, magnetite, cassiterite, and copper.
The formation of placer deposits takes place when the metal-bearing rock on land is weathered and the generated debris is washed down to the sea by the rivers. Further by the action of waves, currents, and rides the particles of heavy metal gets amassed to produce mineral sand deposits. These generally occur as beach deposits.
The answer is; B
Meristem cells are totipotent meaning they can differentiate to any type of plant cells. Therefore they can produce a variety of plant type depending on epigenetic. However, tissue culture is derived from already differentiated cells. Therefore these cells are already determined and can only produce cell type of that plant from which they were derived.
