A. 0
B. 2
C. 4
D. 6
E. 8

Answer: E

Explanation:
Rule:
1. When a number is divided by 10, always a unit place of the number is the remainder.
2. Units place of 2 raised to any power, follows a cyclicity of 4 i.e., Numbers always ends with 2,4,8 and 6 and in the same pattern.
3. So to find the units place of 2 raised to any power, we need to pick the power and divide by 4.
So, if the power when divided by 4 leaves the remainder 1 then its unit place is 2.
Similarly, power when divided by 4 leaves the remainder 2 then its unit place is 4.
Similarly, power when divided by 4 leaves the remainder 3 then its unit place is 8.
And if the power is divisible by 4, then its unit place is 6.
So here,
31 when divided by 4, leaves the remainder 3, so then its unit place is 8.

So, the answer is E.

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