The correct answer is 1 and 2 only. ?Archaeologists have discovered thousands of seals, usually made of steatite, and occasionally of agate, chert, copper, faience and terracotta, with beautiful figures of animals, such as unicorn bull, rhinoceros, tiger, elephant, bison, goat, buffalo, etc. at various sites of Indus valley. The purpose of producing seals was mainly commercial. It appears that the seals were also used as amulets, carried on the persons of their owners, perhaps as modern-day identity cards. Every seal is engraved in a pictographic script which is yet to be deciphered. Signs of planning: bricks, which, whether sun-dried or baked, were of a standardised ratio, where the length and breadth were four times and twice the height respectively. It is a planned settlement that is divided into two sections, one smaller but higher (Citadel) and the other much larger but lower (Lower Town). The Citadel owes its height to the fact that buildings were constructed on mud-brick platforms. It was walled, which meant that it was physically separated from the Lower Town. It had structures that were probably used for special public purposes. The Lower Town was also walled. Several buildings were built on platforms, which served as foundations. The most distinctive features of Harappan cities was the carefully planned drainage system. The roads and streets were laid out along an approximate ‚¬Å“grid‚¬ pattern, intersecting at right angles. It seems that streets with drains were laid out first and then houses built along with them. ?The Lower Town at Mohenjodaro provides examples of residential buildings. The courtyard was probably the centre of activities such as cooking and weaving, particularly during hot and dry weather. The citadel includes the warehouse: a massive structure of which the lower brick portions remain, while the upper portions, probably of wood, decayed long ago and the Great Bath. The Great Bath was a large rectangular tank in a courtyard surrounded by a corridor on all four sides. There were two flights of steps on the north and south leading into the tank, which was made watertight by setting bricks on edge and using a mortar of gypsum.