Einstein’s famous equation which states that mass and energy are interchangeable is?

Question

Accepted Answer

E = mc2. A is correct because E=mc² is Einstein's famous equation relating mass and energy. B is incorrect because the units are mixed up in this formula. C is incorrect because it uses 'M' for energy and 'e' for mass, which is dimensionally wrong. D is incorrect because it incorrectly swaps variables compared to the established formula.