Most plants grow in the a horizon. t f

True

Explanation:

Soils horizons consists of several distinct horizontal layers which are as follows –  

O Horizon -  It is the top, organic layer of soil which is made up leaf litter and humus  

A Horizon – Also known as the topsoil. It lies between the O horizon and the E horizon. In this layer the seeds germinate and the root grows easily as it consists of humus (decomposed organic matter) mixed with mineral particles.

E Horizon – It is the layer is beneath the A Horizon and above the B Horizon. It is made up mostly of sand and silt

B Horizon – This layer is beneath the E Horizon and above the C Horizon. It contains clay and mineral. It is also known as  subsoil.  

C Horizon  It is the layer beneath the B Horizon and above the R Horizon. It is also called regolith and consists of slightly broken-up bedrock.  

R Horizon – It consists of unweathered rock (bedrock) layer