Answer the following question: Information:  - In chemistry, a soap is a salt of a fatty acid. Household uses for soaps include washing, bathing, and other types of housekeeping, where soaps act as surfactants, emulsifying oils to enable them to be carried away by water. In industry they are also used in textile spinning and are important components of some lubricants.  - A sulfonate is a salt or ester of a sulfonic acid. It contains the functional group R-SO.  - A carboxylate is a salt or ester of a carboxylic acid. "Carboxylate salts" have the general formula M(RCOO), where M is a metal and "n" is 1, 2...; "carboxylate esters" have the general formula RCOOR. R and R are organic groups; R  H.  - Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.  - Wetting is the ability of a liquid to maintain contact with a solid surface, resulting from intermolecular interactions when the two are brought together. The degree of wetting (wettability) is determined by a force balance between adhesive and cohesive forces. Wetting deals with the three phases of materials: gas, liquid, and solid. It is now a center of attention in nanotechnology and nanoscience studies due to the advent of many nanomaterials in the past two decades (e.g. graphene, carbon nanotube).  - Hard water is water that has high mineral content (in contrast with "soft water"). Hard water is formed when water percolates through deposits of limestone and chalk which are largely made up of calcium and magnesium carbonates.  - A detergent is a surfactant or a mixture of surfactants with "cleaning properties in dilute solutions." These substances are usually alkylbenzenesulfonates, a family of compounds that are similar to soap but are more soluble in hard water, because the polar sulfonate (of detergents) is less likely than the polar carboxylate (of soap) to bind to calcium and other ions found in hard water.  - Linear alkylbenzene is a family of organic compounds with the formula C6H5CnH2n +1 . Typically , n lies between 10 and 16 , although generally supplied as a tighter cut , such as C12 - C15 , C12 - C13 and C10 - C13 , for detergent use . The CnH2n +1 chain is unbranched . They are sometimes called LABs . They are mainly produced as intermediate in the production of surfactants , for use in detergent . Since the 1960s , LABs have emerged as the dominant precursor of biodegradable detergents .    What object entity has the relation of 'has part' with the subject 'linear alkylbenzene'?   Choices: - 1  - a  - calcium  - carbon  - chemistry  - family  - h  - liquid  - m  - metal  - r  - water
Answer:
carbon