It is supported by evidence from a wide variety of scientific disciplines, including genetics, which shows that different species have similarities in their DNA. There is also evidence supporting the Theory of Evolution in paleontology and geology.
Answer:
Option D, A subject is observed both before and after two exposures to the treatment.
Explanation:
In A-B-A-B design the alphabets have following meaning
a) First A – It is the baseline value or the value measured before treatment
b) First B – It is the treatment measurement
c) Second A - It is the withdrawal of treatment
d) Second B – It is the reintroduction of treatment
The second A is known as the reversal phase in which the intervention is withdrawn to see if the target behavior returns to the baseline behaviour
Thus , there are two measurements involved one before the intervention and second after the intervention
Option D is correct
The answer is a
Hope this helped
The answer to this question is : <span>They tolerate both freshwater and salt water.</span>
