C. Soft or mechanical soft
<span>Penile shaft
</span>During erection, blood<span> flows into the spaces, causing distention and elevation of the penis. The amount of blood entering the penis can be increased by physical or psychological stimulation. As blood enters, there is a temporary reduction in the rate and volume of blood leaving the penis. The arteries carrying blood to the penis dilate; this, in turn, causes tissue expansion. The veins leading from the penis have funnel-shaped valves that reduce the outflow of blood. As the erectile tissue begins to enlarge, the additional pressure causes the veins to be squeezed against the surrounding fibrous tissue, and this further diminishes the outflow of blood. Essentially, blood becomes temporarily trapped in the organ.</span>
The correct answer is letter A. The statement above is true that when animals eat the same type of food they are categorized in the same niche. Niches are ecological communities or ecosystems where specific organisms thrive and fit. Their evolutionary processes are also a result of these different niches found within the environment.
Pressure decreases with increasing altitude.
