The answer is
C because when you combine both A and B, answer states that meeting cannot happen on Friday between 9 AM and 5 PM.
Here is my reasoning:
From (A) : The meeting took place at a certain hour between 9:00 a.m. and 5:00 p.m.
Not sufficient.
From (B) : If the meeting had taken place exactly 66 hours before its actual commencement time, it would have been on a Tuesday
OK. Needs some calculation here. Let us execute with 2 options.
If you can picturize the problem, it becomes easy. Let me try typing in

.
The below numbers are in hours ( for any day):
0 ( beginning of day) 12 ( afternoon) 24 ( End of day)
Tue ( 0 12 24) Wed ( 0 12 24) Thru ( 0 12 24) Fri ( 0 12 24)
Option 01: Beginning of the day
Let us assume meeting starts early morning Friday at 0 Hours. Now go backward:
0 hours(Fri) - 0 hours ( Thur) = 24 hours
0 hours(Thur) - 0 hours(Wed)=24 hours
0 hours ( Wed) - 12 hours ) Tue) = 12 hours
Here already 60 hours is done and if you add 6 hours, it answers that meeting could have happened on Friday
Option 02 : End of day
24 hours(Fri) - 24 hours ( Thur) = 24 hours
24 hours(Thur) - 24 hours(Wed)=24 hours
24 hours ( Wed) - 0 hours ( Wed) = you need another 24 hours!
Therefore, you need 72 hours to reach Tuesday end of day. Hence, the meeting would not have happened on Friday. I hope you understood this

.
Option A and Option B
The problem states meeting happened between 9 AM and 5 PM.
(1) Assume meeting happened at 9 AM Friday.
9 A M(Fri) - 9 AM ( Thur) = 24 hours
9 A M(Thur) - 9 AM(Wed)=24 hours
9 A M ( Wed) - 24 hours (Tue. End of day) = 9 hours
Therfore, 24+24+9 =
57 hours. Hence, meeting didn't take place at 9 AM
(2) Assume meeting happened at 5 PM Friday.
5 P M(Fri) - 5 P M ( Thur) = 24 hours
5 P M(Thur) - 5 P M(Wed)=24 hours
5 P M ( Wed) - 24 hours (Tue. End of day) = 17 hours
Therfore, 24+24+17 =
65 hours. Hence, meeting didn't take place at 5 PM Friday.
Hence, from C, we can exactly arrive at the answer. If in case, the meeting was scheduled at 6 PM, the answer will be correct.
Hope, I was able to explain it properly.
Regards,
Viju