Final answer:
The fraction 5/11 written as a repeating decimal has a 2-digit sequence '45' that repeats indefinitely, making the answer B) 2.
Step-by-step explanation:
When 5/11 is written as a repeating decimal, the goal is to find the number of digits in the smallest sequence of repeating digits. To do this, we need to perform the long division of 5 by 11.
Upon doing the division, we see that the decimal repeats every two digits, which is the sequence '45' and it repeats indefinitely (0.4545...). Therefore, the smallest sequence of repeating digits is 2.