Everyday Science

A stethoscope is a medical instrument used by healthcare professionals to listen to the internal sounds of the body, particularly the heart and lungs. Other options like stereoscope, oscillator, and oncolator are unrelated to this function.

Oil rises up the wick in a lamp due to capillary action, which is the ability of a liquid to flow in narrow spaces without external forces. This phenomenon allows the oil to move upward against gravity through the tiny pores of the wick.

Biogas primarily consists of methane (CH4), which is the main combustible component responsible for its energy content. Other gases like carbon dioxide are present but in smaller amounts, and oxygen is typically absent in biogas.

The scientific study of fingerprints is known as dactylography, which involves analyzing fingerprint patterns for identification purposes. The other options refer to different fields: dactylology is sign language study, dactyliology is not a recognized term, and dialectology is the study of dialects.

Annealing is the process of heating steel to a temperature below red heat and then cooling it slowly to soften the metal and improve its ductility. This matches the description given in the question, making option A correct.

Authoritative nutrition sources such as Eat This Much, FatSecret, FoodStruct, and CalZen consistently report that natural honey contains approximately 304 Calories per 100 grams. This confirms that the correct answer is 'C' (304 Calories). The original question had a mismatch between the correct answer and explanation; the correct answer should be 'C' to match the factual calorie content of honey.

The light from distant stars is affected both by the Earth's atmosphere, which can cause effects like twinkling and absorption, and by interstellar dust, which can scatter and absorb light, causing dimming and reddening.

Beriberi is caused by a deficiency of thiamine (vitamin B1), which is commonly lost when rice is milled, removing the husk where the vitamin is concentrated. Hence, the use of milled rice leads to beriberi.

The chemical symbol for Tungsten is 'W', derived from its alternative name 'Wolfram'. This is the standard symbol used in the periodic table.

Aviculture is the practice of keeping and breeding birds, making option B correct. Apiculture refers to beekeeping, while viniculture and viticulture relate to grape cultivation and winemaking, respectively.