a = "10" → Variable a is assigned the string "10".

b = a → Variable b also holds the string "10" (but it's not used afterward).

a = a * 2 → Since a is a string, multiplying it by an integer results in string repetition.

"10" * 2 results in "1010"

print(a) → prints the new value of a, which is "1010".

✅ Correct answer: D. 1010