Answer:
A
Step-by-step explanation:
In order to compare all three numbers, you must change them all to have the same form, either all decimal form, all fraction, or all percentages.
The easiest ways to compare are decimal and percentage, as they're practically the same thing. For simplicities sake, though, let's turn all the numbers into decimal.
Since 0.85 is already in decimal form, leave it as it is.
3/4 can be turned into a decimal by putting it into a calculator, but intuitively you should know that it's 0.75. If you don't know a fraction intuitively, you just need to make the fraction into a multiple of denominator 100 and take the numerator. For example:

Numerator is 75.0, now simply move the decimal place up to to get the decimal form 0.75.
91% can be changed into a decimal by moving the decimal place left 2 places. 91.0% turns into 0.91.
Now that you can see the numbers, just rearrange them from least to greatest
0.75<0.85<0.91
equal to A
Answer:
Jon lost a total of 3 kilograms in these 3 months.
Step-by-step explanation:
Weight that Jon gained in December = 2.2 kilograms
Weight that Jon lost in January = 1.5 kilograms
Weight that Jon lost in February = 3.7 kilograms
Overall Change in his weight = Total Weight he gained - Total weight he Lost
Total weight he gained is 2.2 kilograms as he only gained weight in December. Total weight he lost will be sum of weights he lost in January and February.
So, total weight Jon lost = 1.5 + 3.7 = 5.2 kilograms
Thus,
Total change in Jon's Weight = 2.2 - 5.2 = -3.0 kilograms
This shows that Jon lost a total of 3 kilograms in these 3 months.
Conclusion:
The statement that best describe the total change in his weight is: Jon lost a total of 3 kilograms in these 3 months