Which of the following is 2.45986 rounded to 3 significant
digits?

The rounded three digits for the given number is 2.46

Explanation:

Significant figures are the number of digits in a value which contributes to the degree of accuracy of the value while measuring

Rules:

Digits which are not zero are always essential. Any zeros between two major digits are important. Only a final zero or trailing zeros are important in the decimal section

Solution:

Given number-  2.45986Decimals- 5 digitsScientific Notation -2.45986 × 10^0Applying the rules until rounding the 3 digits we get,The rounded three digits for the given number is 2.46