A. 0
B. 1
C. 4
D. 6
E. 8

Answer: D

Explanation:
Concept:
Every digit (0,1,2, 3,…..9) when raised to a power follows a pattern, i.e., there is a cyclicity in the values of units digits when raised to powers.
The pattern for 4:
4^1 - 4
4^2 - 16
4^3 - 64
4^4 - 256
So, if we look at it the unit’s digit pattern for 4 raised to a positive integer is 4 and 6 in that order.
4^{odd} - 4
4^{even} – 6
Given,
Unit’s place of 4^{1555!}
Note that,
n!=n*n-1*…3*2*1
1555!=1555*1554*…3*2*1
So, it’s even. In fact, n! is always even for all the values of n ≥ 2

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