The b horizon is also called the a. topsoil b. subsoil c. partially altered parent material d. unaltered parent material

B. subsoil

Explanation:

A soil horizon can be define as the parallel layer of the soil which differs in texture, color and composition based upon the physical, chemical and biological activities. A typical soil horizon varies from layers above and beneath. The B horizon is called as a subsoil. It is typically comprise of high inorganic mineral density. It is developed by the process of pedogenesis. The inorganic minerals such as iron oxides, and clay are predominately present in this horizon. It is typically reddish to brownish in color due to high concentration of iron oxides.

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.