Why might some people be opposed to the use of biotechnology?
a.
it can lead to the development of resistant microorganisms.
b.
it can lead to competition between modified and native organisms.
c.
it can lead to the production of toxic materials.
d.
all of the above

Biotechnology is science which uses biological processes in order to produce useful products or organisms with desired trait or characteristics.

It includes the manipulation of the genome of an organism.  

It helps in making products like insulin and genetically modified plants such as Bt cotton, golden rice et cetera.

However, it has many serious drawbacks as it includes the manipulation of the genome of an organism.

It can result in the development of resistant microorganism, for example, development of the superbug due to overuse of antibiotics.

Similarly, it can result in the production of toxic materials.

Thus, option d. all of the above would be the correct answer.

what's the rest of the question

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products