All the statements about extrinsic motivation is not true except
a. extrinsic motivation can be positive or negative.
b. extrinsic motivation is compelled by one’s own enjoyment.
c. extrinsic motivation is the same as self-motivation.
d. participation in a hobby is usually driven by extrinsic motivation.

"acknowledging a right to benefit from the presence of animals requires government action to ensure human access to animals in a number of different spheres," writes jessica pierce, ph.d., in psychology today. the pragmatic meaning of the term "right" in this statement is

Cells destroy body cells infected by a virus or bacteria.

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.