In an embryo, the tissues that receive a nerve produce sprouting
factor, which encourages nerves to grow and branch, while
the nerve produces anti-sprouting factor, which inhibits nerve
growth. this is an example of a. a positive feedback system
b. a negative feedback system c. thermoregulation
d. homeostasis.

Answer : The correct answer is -

b. a negative feedback.

Negative feedback is a mechanism of regulation for physiological functioning in the living systems.

It causes decline /reduction in the response by a particular stimulus.

As per the question, the production of nerve (through sprouting factor) causes it to release anti sprouting factor, which leads to the inhibition of nerve growth.

In other words, the stimulus anti sprouting factor (released by nerve) causes the decline of nerve growth.

Thus, it is an example of negative feedback.

fabric is silk wool ext. paper isnt

explanation:

u cant make fabric out of paper cause paper comes from wood while fabric comes from animals

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus