The technique of communication by signs made with the fingers is called

Answer: Option C

Explanation:

The use or study of images or symbols in visual arts is called Iconography.

Literature dealing with saints is called Hagiology.

The treatment of illness through the use of water, either internally or through external means such as steam baths is called Hydropathy.

Answer: Option A

Explanation:

The science of the nature of heavenly bodies is called Cosmogony.

The science that describes and maps the main features of the universe is called Cosmography.

The science of the nature, origin and history of the universe is called Cosmology.

Answer: Option C

Explanation:

The supposed communication of thoughts or ideas by means other than the known senses is called Telepathy.

The study of caves is called Spelelogy.

The branch of science concerned with earthquakes and related phenomena is called Seismology.

Answer: Option D

Explanation:

The study of ancient writing systems and the deciphering and dating of historical manuscripts is called Paleography.

A person's facial features or expression, esp. when regarded as indicative of character or ethnic origin is called Physiognomy.

The production of silk and the rearing of silkworms for this purpose is called Sericulture.

Answer: Option B

Explanation:

The study of visual imagery and its symbolism and interpretation is called Iconology.

The practice of compiling dictionaries Lexicography

The study or collection of coins, paper currency, and medals is called Numismatics.