$A$ scientist claims to have a perfect technique in which he can spontaneously convert an electron completely into energy in the laboratory without any other material required. What is the conclusion about this claim from our current understanding of physics?

• A
  This is possible because Einstein's equation says that mass and energy are equivalent... it is just very difficult to achieve with electrons
• B
  This is possible and it is done all the time in the high-energy physics labs.
• C
  The scientist is almost correct... except that in converting the electron to energy, an electron's anti-particle is produced in the process as well
• D
  This is not possible because charge conservation would be violated.