Raid 5 Explanation

I am currently running Raid-5 in a 3 disk scenario.  My Dell Server has 6 disk drive slots.

I understand if one disk fails, the other two will continue to function fine.

I will be adding 3 addtional drives for a total of 6.

Which of the following two assumptions is correct:

Assumption A:

In a 6 disk (Raid-5) scenario, if one drive is lost, the other five will function fine.  The Server would then "rebuild" redundancy in a 5 disk scenario.

If 2 drives fail, 4 would run fine under Raid-5
If 3 driver fail, 3 would run fine under Raid-5
If 4 drives fail, 2 would run fine under Raid-5
If 5 drives were lost, all data would be lost

Assumption B:

If any two of the six drives fail, all data would be lost.

Thanks for your help.