Answer:
b) 1.776 × 10^-4
Explanation:
a) 1.776 × 10^-3 is 0.001776 (3 places to the right)
b) 1.776 × 10^-4 is 0.0001776 (4 places to the right)
And the rest of the options go with a different number so there is no way they can be expressed as 0.0001776.
Therefore, the correct answer is b.