<Table> <Tr> <Td> </Td> <Td> O ) Organic matter : Litter layer of plant residues in relatively undecomposed form . <P> A ) Surface soil : Layer of mineral soil with most organic matter accumulation and soil life . This layer eluviates ( is depleted of ) iron , clay , aluminium , organic compounds , and other soluble constituents . When eluviation is pronounced , a lighter coloured `` E '' subsurface soil horizon is apparent at the base of the `` A '' horizon . A-horizons may also be the result of a combination of soil bioturbation and surface processes that winnow fine particles from biologically mounded topsoil . In this case , the A-horizon is regarded as a `` biomantle '' . </P> <P> B) Subsoil : This layer accumulates iron , clay , aluminium and organic compounds , a process referred to as illuviation . </P> <P> C ) Parent rock : Layer of large unbroken rocks . This layer may accumulate the more soluble compounds . </P> R ) bedrock : R horizons denote the layer of partially weathered bedrock at the base of the soil profile . Unlike the above layers , R horizons largely comprise continuous masses ( as opposed to boulders ) of hard rock that can not be excavated by hand . Soils formed in situ will exhibit strong similarities to this bedrock layer . </Td> </Tr> </Table>
<Table> <Tr> <Td> </Td> <Td> O ) Organic matter : Litter layer of plant residues in relatively undecomposed form . <P> A ) Surface soil : Layer of mineral soil with most organic matter accumulation and soil life . This layer eluviates ( is depleted of ) iron , clay , aluminium , organic compounds , and other soluble constituents . When eluviation is pronounced , a lighter coloured `` E '' subsurface soil horizon is apparent at the base of the `` A '' horizon . A-horizons may also be the result of a combination of soil bioturbation and surface processes that winnow fine particles from biologically mounded topsoil . In this case , the A-horizon is regarded as a `` biomantle '' . </P> <P> B) Subsoil : This layer accumulates iron , clay , aluminium and organic compounds , a process referred to as illuviation . </P> <P> C ) Parent rock : Layer of large unbroken rocks . This layer may accumulate the more soluble compounds . </P> R ) bedrock : R horizons denote the layer of partially weathered bedrock at the base of the soil profile . Unlike the above layers , R horizons largely comprise continuous masses ( as opposed to boulders ) of hard rock that can not be excavated by hand . Soils formed in situ will exhibit strong similarities to this bedrock layer . </Td> </Tr> </Table>
which of the following is the designation for bedrock a. o b. a c. r d. c
which of the following is the designation for bedrock a. o b. a c. r d. c
R
R