Answer:
Option D, Number of limbs
Explanation:
Options for the question
a. Birth weight
b. Hair color
c. Number of offspring
d. Number of limbs
Solution
Variation within a species is caused due to genetic differences governed by varying allele frequencies and duet to environmental factors that somewhere effect the expression of the genetic potentials thereby causing phenotypic variation.
Number of limbs is a physical characteristics, very unlikely governed by genetic variation. While factors such as hair color (grey, black, white etc.), height (tall, short, medium) etc. are governed by genetic variation as a result of which they have several phenotypic variations.
Hence, option D is correct
I think the best way to remove mud from water is reverse osmosis. But if your're think about doing it by hand than I would boil the water so the mud collects on the bottom. Then I would put a plastic wrap on top of the container while a small cup is inside the bowl. And then put a rock on the plastic wrap in the center on top of cup.
Explanation: The water vapor rises because of vaporization, and then collects as condensation and drips into cup-collection as pure water
I got this from a lab i did before, so all credits don't go to me =><span />