What is difference between Bed rock and parent rock??its urgent

Parent rock (C - horizon)

Below the subsoil is the parent rock or C - horizon, which consists of small pieces of rocks with cracks and crevices. The particles of rocks found in soil come from weathered rock in the C - horizon. 

Below this is solid rock called bedrock. It is non - porous. Rainwater gathers over it to form the water table

Bedrock essentially refers to the substructure composed of hard rock exposed or buried at the earth's surface; an exposed portion of bedrock is often called an outcrop. Bedrock may have various chemical and mineralogical compositions and can be igneous, metamorphic or sedimentary in origin.Parent rock, also referred to as substratum, refers to the original rock from which something else was formed. It is mainly used in the context of soil formation where the parent rock (or parent material) normally has a large influence on the nature of the resulting soil