The type of material makes up the functional aspect of the transducer that creates the high-frequency sound is Crystals which is a ceramic.
Step-by-step explanation:
High frequency of sound can be produced in the transducer with the help of materials like ceramic materials.These are non-metallic compounds. The ceramic materials are those that are brittle in nature. Crystals, glasses are some of the examples of ceramic materials.
Ceramic materials like crystals are used in transducers that makes them functionally fit to produce high frequency sounds. The materials that are given in the options tungsten, iron oxide and silver/chromium alloy are not fit for these type of materials manufacturing. These belongs to metals and metal oxides and alloy types of metals.