Answer:
adding a catalyst
Explanation:
catalysts accelerate the speed of chemical reactions
The answer to this question is A
I believe the answer is C.
Answers
When doing medical research with human subjects, the following are unavoidable limitations;
It’s often impossible to repeat trials on the same subjects.
Subjects may report an inaccurate medical history.
It can be difficult to control all possible variables
There are ethical or privacy concerns to consider.
Explanation
When doing a medical research that involves human subjects it should be voluntary, informed and consent. The researchers should respect the persons treated as autonomous agents. The volunteers should be protected from physical, mental and emotional harm. The benefits should outweigh the costs.
A Nonsense mutation. It changes a codon coding for an amino acid to a codon coding for the signal to stop or terminate translation