Which of the following statements about gamma rays is true?

• A. Gamma rays consist of high photons which do not have a mass but a charge equal to that of an electron.
• B. Gamma rays consist of low-energy photons of high wavelength.
• C. Gamma rays consist of high-energy photons with a high penetration power.
• D. Gamma rays are short bursts of very high-energy electrons.
• E. Gamma rays consist of high-energy photons with a low penetration power.