The unit digit in \(7^{153}\) is?
Answer: C
\(7^{153} = \left ( 7^{4}\right )^{38}\times 7\) Now, unit digit of \(\left ( 7^{4}\right )^{38} = 1\) Therefore, unit digit of \(7153 = 1 \times 7\) \(= 7\)