Which makes viral infections difficult to defend?
a.) the immune system must attack the body’s own cells

b.) viruses are attacked by a nonspecific immune response

c.) viruses live outside of cells

d.) macrophages work slowly

Viral infections are difficult to defend as viruses are attacked by a nonspecific immune response.

Explanation:

sand 60

clay 10

silt 30

sandy loam should be dominated by the sand. as the amount of sand increased, the amount of slit needed to anchor the plants' roots to the sand will also be increased. even though the amount is very little, 10% part of clay is still necessary for proper oxidation.

answer; atp and nadph;