If e is the symbol for an element, which two of the following symbols represent isotopes of the same element?

If E is the symbol for an element,  the two symbols which represent isotopes of the same chemical element are: A and D.

Isotopes can be defined as two or more forms of a chemical element that comprises equal atomic number (numbers of protons) and electrons but different numbers of neutrons.

The isotope of an element is denoted by

Where;

If the mass number = 20

Atomic number (numbers of protons) = 10

Number of neutron = 10

Note: The answer option with the same atomic number (numbers of protons) but different mass number is A and D.

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A and D

Explanation: isotopes must have same atomic number but different mass number due to the difference in their Neutron number