Some statements about crystals are given below: [P]: The crystal lattice is constructed from repeating units called unit cells. [Q]: The external appearance of a crystal is described by crystal habits, such as needles, prisms, rosettes etc. [R]: Polymorphism is the ability of a compound to crystallize as more than one distinct crystalline species with different internal lattice. [S]: Hydrates are always more soluble than anhydrous form of the same drug. Choose the corrected combination of statements about crystals.