The external cell membrane. Even organisms as simple as bacteria have a cell membrane.
Prokaryotes do not have internal membranes but they still have external membranes.
Everything living thing has a cell membrane
The way in which you need to solve this is by using the formula:
<span>R = ρL/A
</span>That one is the formula that demonstrates <span>Resistance of a wire in Ω.
The formula can be explained like this:
</span><span>ρ is resistivity of the material in Ω-m </span>
<span>L is length in meters </span>
<span>A is cross-sectional area in m² </span>
<span>A = πr², r is radius of wire in m
As soon as you have your numbers, you can replace and proceed to get the asnwer</span>
I think the answer is A! i might be wrong