________ is considered one among the oldest methods to achieve required shapes of metals.

Explanation:

Forging is a process in which material is shaped by the application of localized compressive forces exerted manually or with power hammers, presses, or special forging machines. The process may be carried out on materials in either hot or cold state.

There are following types of forging:

• Smith Forging
• Drop Forging
• Press forging

​Welding

• Welding is a process of joining two similar or dissimilar metals by fusion, with or without the application of pressure and with or without the use of filler metals.
• The fusion of metal takes place by means of heat.
• The heat may be obtained from electric arc, electric resistance, chemical reaction, friction, or radiant energy.
• Based on the composition of joints, the joining process may be classified as:
• Solid-state welding: It is also called as Autogenous welding
• It is classified into:
  • Explosive Friction
  • Ultrasonic welding
  • Diffusion welding
  • Friction welding
  • Forge welding
• Liquid state welding: It is also called as Homogeneous welding
• It is classified into:
  • Resistance welding
  • Arc welding
  • TIG welding
  • MIG welding
  • PAW welding
  • Gas welding
• Solid/Liquid state welding: It is also called as Heterogeneous welding
• It is classified into:
  • Brazing
  • Soldering

Lapping:

• It is an abrading process for refining surface finish and the geometrical accuracy of flat cylindrical and spherical surfaces
• It is a process or removing surface roughness, tool marks, surface cracks from grinding, slight distortions and other minor – defects from previous operations
• Lapping produces geometrically true surfaces, corrects minor surface imperfections, improves dimensional accuracy and provides a very close fit between two contact surfaces

Annealing

• It is a heat treatment process in which the material is taken to a high temp, kept there for some time, and then cooled in the furnace itself.
• Cooling is done slowly to avoid the distortion.
• The benefits of annealing are:
  • Relieve stresses
  • Increase softness, ductility, and toughness
  • Produce a specific microstructure
  • Improve machining characteristic

Therefore, from the given options, forging is one among the oldest methods to achieve required shapes of metals.