The correct answer is option 'C' - urea.

Urea was the first organic compound to be synthesized in the laboratory in 1828 by Friedrich Wöhler, a German chemist. This discovery marked a significant milestone in the field of organic chemistry and led to the realization that organic compounds could be produced from inorganic materials.

Now let's understand why the other options are incorrect:

a) Alcohol: While alcohols are organic compounds, they were not the first ones to be synthesized in the laboratory. Alcohol synthesis had been known for a long time before urea was synthesized.

b) Acetic Acid: Acetic acid is another organic compound, commonly known as vinegar. However, it was not the first organic compound to be synthesized in the laboratory.

c) Urea: Urea, with the chemical formula CO(NH2)2, is an organic compound that is found in urine and other bodily fluids. It is a key component of the nitrogenous waste product excreted by mammals, including humans. Urea was synthesized by Wöhler from inorganic materials, namely ammonium cyanate, which was formed by the reaction of silver cyanate and ammonium chloride.

The synthesis of urea from inorganic materials was a groundbreaking achievement because it challenged the prevailing belief of vitalism, which suggested that organic compounds could only be produced by living organisms. Wöhler's synthesis of urea demonstrated that organic compounds could be artificially produced in the laboratory, thus providing evidence against vitalism and paving the way for further advancements in organic chemistry.

In conclusion, urea was the first organic compound to be synthesized in the laboratory, marking a significant milestone in the field of organic chemistry.