The correct answer is option (A) Variation in the strawberry plants.
When the effect of fertilizer on the growth of two strawberry plants is tested, unavoidable source of experimental error is the variation in the strawberry plants. Variation refers to the deviation or differences from the normal plant which can be due to genetic variation. It is due to change in the DNA sequence. If any one of the two plants being tested show variation, the rate of metabolism differs and changes the growth pattern of the plant. The rate of absorption of water and nutrients is effected which brings change in the growth of the plant and causes an error in the experiment and the result.
<span>They are organelle, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystem, and biosphere.</span>
<h2>Answer:</h2>
Carbon
<h2>Explanation:</h2>
Carbon is essential part of living organisms. Scientist use carbon isotopes for dating purposes but the problem with carbon isotopes is also limited as Carbon dating only works for objects that are younger than about 50,000 years, and most rocks of interest are older than that
It includes killing bacteria and storing partially digested food
