Block an interrogation to eliminate last cause of slippage (6,4)
I believe the answer is:
banana skin
'cause of slippage' is the definition.
'banana skin' can be an answer for 'cause' (I have seen 'cause of embarrassment' mean 'banana skin' so perhaps 'cause' could also mean 'banana skin'). I am unsure of the 'of slippage' bit.
'block an interrogation to eliminate last' is the wordplay.
I cannot really understand how this works, but
'block' could be 'ban' (I've seen this in another clue) and 'ban' is located in the answer.
'an' could be 'i' (Roman numeral for one) and 'i' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for banana skin that I've seen before include "pedestrian problem" , "that could lead to one's downfall" , "slipper" , "Something to slip up on" , "Potential downfall" .)