<span>If a scientist is trying to determine whether the use of cell phone contributes to brain cancer, then the most significant weakness in this type of study is the relationship between the cell phone and brain cancer itself. It is hard to identify its connections and consequences with each other.</span>
I believe the answer is B.
Weathering: Weathering occurs in situ (on site, with little or no movement), and should not be confused with erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity. Weathering processes are divided into physical and chemical weathering.
erosion: Erosion happens when rocks and sediments are picked up and moved to another place by ice, water, wind or gravity. Mechanical weathering physically breaks up rock. One example is called frost action or frost shattering. ... The sediment is dropped, or deposited, in landforms.
deposition: Deposition is the processes where material being transported by a river is deposited. Deposition occurs when a river loses energy. This can be when a river enters a shallow area (this coud be when it floods and comes into contact with the flood plain) or towards its mouth where it meets another body of water.
<span>The
filoviruses are deadly because their first target are the
immunological (white) cells whose function is defend the body against
foreign threats. The early target cells of a filovirus are: monocytes
which are the largest type of white cell, macrophages which are the
white cells responsible of locating and eating microscopic foreign
bodies, and dendritic which are the white cells in char of processing
antigen material.</span>
