There are ten possible digits in our decimal system, but how many digits are available for use in the binary number system?

2 is the correct answer for the above question.

Explanation:

In the decimal number system, there are 10 digits which starts from 0 and ends with 9 because the base of this number system is 10.It means that the digits of a number system are depended on the base of that number system. For example, if there is 4 base of any number system then there are 4 digits lies on that number system which starts from 0 and ends on 3.So the binary system has 2 digits which starts from 0 and ends with 1 because the base of this number system is 2. Hence the answer is 2.