X-radiation (composed of X-rays) is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. They are shorter in wavelength than UV rays and longer than gamma rays. In many languages, X-radiation is called Röntgen radiation, after Wilhelm Röntgen, who is usually credited as its discoverer, and who had named it Xradiation to signify an unknown type of radiation.

Correct Option: B

X-radiation (composed of X-rays) is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. They are shorter in wavelength than UV rays and longer than gamma rays. In many languages, X-radiation is called Röntgen radiation, after Wilhelm Röntgen, who is usually credited as its discoverer, and who had named it Xradiation to signify an unknown type of radiation.

The smallpox vaccine was the first successful vaccine to be developed. The process of vaccination was first publicised by Edward Jenner in 1796, who acted upon his observation that milkmaids who caught the cowpox virus did not catch smallpox. Before the introduction of a vaccine, the mortality of the severe form of smallpox—variola major—was very high. Historical records show that a method of inducing immunity was already known. A process called inoculation, also known as insufflation or variolation was practiced in India as early as 1000 BC.

Correct Option: B

The smallpox vaccine was the first successful vaccine to be developed. The process of vaccination was first publicised by Edward Jenner in 1796, who acted upon his observation that milkmaids who caught the cowpox virus did not catch smallpox. Before the introduction of a vaccine, the mortality of the severe form of smallpox—variola major—was very high. Historical records show that a method of inducing immunity was already known. A process called inoculation, also known as insufflation or variolation was practiced in India as early as 1000 BC.

Sir James Young Simpson was a Scottish and an important figure in the history of medicine. Simpson discovered the anaesthetic properties of chloroform and successfully introduced it for general medical use. Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous. Several million tons are produced annually as a precursor to Teflon and refrigerants, but its use for refrigerants is being phased out.

Correct Option: A

Sir James Young Simpson was a Scottish and an important figure in the history of medicine. Simpson discovered the anaesthetic properties of chloroform and successfully introduced it for general medical use. Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous. Several million tons are produced annually as a precursor to Teflon and refrigerants, but its use for refrigerants is being phased out.

The Lumière brothers, Auguste Marie Louis and Louis Jean were the earliest filmmakers in history. The Lumières held their first private screening of projected motion pictures in 1895. Their first public screening of films at which admission was charged was held on December 28, 1895, at Salon Indien du Grand Café in Paris.

Correct Option: B

The Lumière brothers, Auguste Marie Louis and Louis Jean were the earliest filmmakers in history. The Lumières held their first private screening of projected motion pictures in 1895. Their first public screening of films at which admission was charged was held on December 28, 1895, at Salon Indien du Grand Café in Paris.

Joseph Aspdin, a British bricklayer from Leeds, is considered to be the originator of Portland cement. A process for the manufacture of Portland cement was patented in 1824. This cement was an artificial cement similar in properties to the material known as "Roman cement.” Aspdin's process was similar to a process patented in 1822 and used since 1811 by James Frost who called his cement "British Cement".

Correct Option: C

Joseph Aspdin, a British bricklayer from Leeds, is considered to be the originator of Portland cement. A process for the manufacture of Portland cement was patented in 1824. This cement was an artificial cement similar in properties to the material known as "Roman cement.” Aspdin's process was similar to a process patented in 1822 and used since 1811 by James Frost who called his cement "British Cement".