two
A DNA molecule consists of two long polynucleotide chains composed of four types of nucleotide subunits.
If your choices are the following:
<span>a. A
b. B
c. C
d. D
</span>
Then the answer is C. Interneurons<span> create neural circuits so that there is a communication between sensory or motor </span>neurons<span> and the central nervous syste</span>
D. <span>controlled
is the right answer because a</span><span>n </span>experiment<span> in which an observer tests a hypothesis by looking for changes carried by alterations to a variable.</span>