Which of the following is false regarding soils?

A. They usually require centuries or millennia to form.
B. Soils rich in organic matter are usually dark in color.
C. Older soils usually have fewer horizons than younger soils.
D. Their properties are affected by the type of rock from which they form.
E. Their development is affected by climate and organisms.

Option C, Older soils usually have fewer horizons than younger soils.

Explanation:

Older soils have well expressed soil horizons it is because old soil consists of distinctive layer of deposits including both organic and inorganic material which undergo stratification with time. The longer the time duration, the better stratified the soil is and hence more clear and distinctive are its horizons.  

However in case of new soil, the horizon is not distinctive because of incomplete stratification.  

hence, option C is correct