(A) On average, the office employees working at home for a day work fewer hours than office employees working at the office.
>>>>> Statement says only 25% work less than one hour, then 75% of them work more than one hour. So it cannot be determined that the ones working from home for a day work less than one working at the office.
(B) 10 percent of the office employees are less productive working from home than working in their office.
>>> This is not true since 90% of the 25%(about 22%) of the employees working from home believe they are more productive.
(C) At least 15 percent of the office employees do not define productivity exclusively in terms of the number of hours worked.
>>>> Correct. Since 90% of the 25%(about 22%) believe they are more productive even though they work less than one hour working from home, they do not seem to define productivity in terms of number of hours worked.
(D) At least 25 percent of the office employees can complete the same amount of work in one hour at home as in 8 hours at the office.
>>>> The statement does not provide any information for this to be true. It say only that they believe they are more productive.
(E) Some of the office employees make statements regarding their productivity that are not in fact true.
>>>> This goes beyond the statement. There is no reason to believe this is true from the given statement.

25% of the employees actually work less than 1 hr means around 75% work more than 1 hour.
At the same time 90% of the employees believe they are more productive working at home.
So at least 90%-75%= 15% of the employees who work less than 1 hour think they are more productive working at home than working in their office which can be indirectly interpreted as the definition described in the choice C
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