What material has a high melting point, a high atomic number, and is used as a target material to produce x-rays?

Tungsten is the correct answer because it possesses the necessary properties that make it an ideal target material for x-ray production. It has a very high melting point of around 3,422 degrees Celsius, which allows it to withstand the intense heat generated when high-speed electrons collide with it in x-ray tubes. This property is essential for maintaining the integrity of the target material under operating conditions.

Additionally, tungsten has a high atomic number of 74, which is beneficial for x-ray production. A higher atomic number increases the efficiency of x-ray generation, as it enhances the likelihood of electron interactions that result in x-ray emission. The efficiency and quality of the x-rays produced are critical for medical imaging and other applications that rely on x-ray technology.

In contrast, while gold and silver may also produce x-rays, they do not have the same combination of high melting points and atomic numbers that tungsten has, making them less suitable for this application. Lead, though having a high atomic number and density, is primarily used for shielding against radiation rather than as a target for x-ray production. Therefore, tungsten is clearly the material of choice for effective and safe x-ray generation.